diff --git a/CHANGELOG.md b/CHANGELOG.md
index 628b882..7d4697d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,10 @@
 
 ### Fixed
 
+- Catalog-managed dependencies no longer produce a broken "How to Update" instruction in generated GitHub and Linear issues.
+    - Previously, when a provider had no catalog file path available, the instruction rendered nonsense: either ``Edit `undefined`:`` or an "Edit" line with empty backticks and no filename.
+    - Issues now fall back to generic wording ("managed in the catalog. Update it in the catalog:") when the catalog file is unknown, and still show the exact file (e.g. ``Edit `pnpm-workspace.yaml`:``) when it is known.
+    - Both single-dependency and grouped issues are covered. A new `normalizeCatalogFile` helper (exported from `@dependicus/core`) treats missing, empty, and the literal `"undefined"`/`"null"` strings as "no catalog file".
 - Fix version numbers without `.` failing to match open tickets, resulting in duplicates
 
 ### Removed
diff --git a/src/core/index.ts b/src/core/index.ts
index d9ed9a4..043c4e5 100644
--- a/src/core/index.ts
+++ b/src/core/index.ts
@@ -37,6 +37,7 @@ export {
     formatSizeChange,
     sanitizeCacheKey,
     convertGitUrlToHttps,
+    normalizeCatalogFile,
 } from './utils/formatters';
 
 export {
diff --git a/src/core/utils/formatters.test.ts b/src/core/utils/formatters.test.ts
index 371c6d0..8ec1a05 100644
--- a/src/core/utils/formatters.test.ts
+++ b/src/core/utils/formatters.test.ts
@@ -8,6 +8,7 @@ import {
     convertGitUrlToHttps,
     formatBytes,
     formatSizeChange,
+    normalizeCatalogFile,
 } from './formatters';
 
 describe('sanitizeCacheKey', () => {
@@ -25,6 +26,28 @@ describe('sanitizeCacheKey', () => {
     });
 });
 
+describe('normalizeCatalogFile', () => {
+    it('returns a real path unchanged (trimmed)', () => {
+        expect(normalizeCatalogFile('pnpm-workspace.yaml')).toBe('pnpm-workspace.yaml');
+        expect(normalizeCatalogFile('  package.json  ')).toBe('package.json');
+    });
+
+    it('returns undefined for a missing path', () => {
+        expect(normalizeCatalogFile(undefined)).toBeUndefined();
+        expect(normalizeCatalogFile(null as unknown as string)).toBeUndefined();
+    });
+
+    it('returns undefined for empty or whitespace-only paths', () => {
+        expect(normalizeCatalogFile('')).toBeUndefined();
+        expect(normalizeCatalogFile('   ')).toBeUndefined();
+    });
+
+    it('treats the literal strings "undefined" and "null" as missing', () => {
+        expect(normalizeCatalogFile('undefined')).toBeUndefined();
+        expect(normalizeCatalogFile('null')).toBeUndefined();
+    });
+});
+
 describe('formatDate', () => {
     it('formats ISO date to YYYY-MM-DD', () => {
         expect(formatDate('2024-03-15T10:30:00.000Z')).toBe('2024-03-15');
diff --git a/src/core/utils/formatters.ts b/src/core/utils/formatters.ts
index 82a9e7a..f7e80c7 100644
--- a/src/core/utils/formatters.ts
+++ b/src/core/utils/formatters.ts
@@ -8,6 +8,28 @@ export function sanitizeCacheKey(str: string): string {
     return str.replace(/[^a-zA-Z0-9._-]/g, '_');
 }
 
+/**
+ * Normalize a provider's catalog file path for display in issue templates.
+ *
+ * Returns `undefined` for values that would render as a broken instruction such
+ * as `Edit ``:` or `Edit `undefined`:`. That covers a genuinely missing path
+ * (`undefined`/`null`), an empty/whitespace-only string, and the literal strings
+ * `"undefined"`/`"null"` (which can leak in when an upstream value was
+ * string-interpolated before reaching the template). Callers should treat a
+ * `undefined` result as "no specific catalog file" and fall back to generic
+ * wording.
+ */
+export function normalizeCatalogFile(catalogFile: string | undefined): string | undefined {
+    if (catalogFile === undefined || catalogFile === null) {
+        return undefined;
+    }
+    const trimmed = catalogFile.trim();
+    if (trimmed === '' || trimmed === 'undefined' || trimmed === 'null') {
+        return undefined;
+    }
+    return trimmed;
+}
+
 export function formatDate(isoDate: string | undefined): string | undefined {
     if (!isoDate) {
         return undefined;
diff --git a/src/github-issues/issueDescriptions.test.ts b/src/github-issues/issueDescriptions.test.ts
index 7897af8..83d5968 100644
--- a/src/github-issues/issueDescriptions.test.ts
+++ b/src/github-issues/issueDescriptions.test.ts
@@ -339,6 +339,38 @@ describe('buildIssueDescription', () => {
         expect(result).toContain('test-pkg: 2.0.0');
         expect(result).not.toContain("'test-pkg'");
     });
+
+    it('avoids a broken catalog file reference when catalogFile is missing', () => {
+        const dep = makeDependency();
+        const store = makeStore(dep);
+        const { catalogFile: _catalogFile, ...providerInfoWithoutCatalogFile } = npmProviderInfo;
+        const result = buildIssueDescription({
+            dep: dep,
+            store: store,
+            minVersion: '1.1.0',
+            effectiveLatestVersion: '2.0.0',
+            getDetailUrl: testGetDetailUrl,
+            providerInfo: providerInfoWithoutCatalogFile,
+        });
+        expect(result).toContain('managed in the catalog');
+        expect(result).not.toContain('Edit ``');
+        expect(result).not.toContain('undefined');
+    });
+
+    it('treats a literal "undefined" catalogFile as missing', () => {
+        const dep = makeDependency();
+        const store = makeStore(dep);
+        const result = buildIssueDescription({
+            dep: dep,
+            store: store,
+            minVersion: '1.1.0',
+            effectiveLatestVersion: '2.0.0',
+            getDetailUrl: testGetDetailUrl,
+            providerInfo: { ...npmProviderInfo, catalogFile: 'undefined' },
+        });
+        expect(result).toContain('managed in the catalog');
+        expect(result).not.toContain('Edit `undefined`');
+    });
 });
 
 describe('buildGroupIssueDescription', () => {
@@ -429,6 +461,29 @@ describe('buildGroupIssueDescription', () => {
         expect(result).toContain('react: 2.0.0');
     });
 
+    it('avoids a broken catalog file reference in groups when catalogFile is missing', () => {
+        const group: OutdatedGroup = {
+            groupName: 'test-group',
+            dependencies: [makeDependency({ name: 'react' })],
+            owner: 'myorg',
+            repo: 'myrepo',
+            policy: { type: 'dueDate' },
+            worstCompliance: { updateType: 'major', daysOverdue: 0, thresholdDays: 360 },
+        };
+
+        const store = makeGroupStore(group);
+        const { catalogFile: _catalogFile, ...providerInfoWithoutCatalogFile } = npmProviderInfo;
+        const result = buildGroupIssueDescription({
+            group: group,
+            store: store,
+            getDetailUrl: testGetDetailUrl,
+            providerInfoMap: new Map([['npm', providerInfoWithoutCatalogFile]]),
+        });
+        expect(result).toContain('Update each dependency in the catalog');
+        expect(result).not.toContain('`` catalog');
+        expect(result).not.toContain('undefined');
+    });
+
     it('quotes scoped package names in group catalog YAML', () => {
         const group: OutdatedGroup = {
             groupName: 'scoped-group',
diff --git a/src/github-issues/issueDescriptions.ts b/src/github-issues/issueDescriptions.ts
index b04c43f..d24c03b 100644
--- a/src/github-issues/issueDescriptions.ts
+++ b/src/github-issues/issueDescriptions.ts
@@ -6,6 +6,7 @@ import {
     findFirstVersionOfType,
     formatBytes,
     formatSizeChange,
+    normalizeCatalogFile,
     resolveUrlPatterns,
 } from '../core/index';
 import { helpers } from './templates/helpers';
@@ -113,7 +114,8 @@ export function buildIssueDescription({
         };
     });
 
-    const { installCommand, supportsCatalog, catalogFile } = providerInfo;
+    const { installCommand, supportsCatalog } = providerInfo;
+    const catalogFile = normalizeCatalogFile(providerInfo.catalogFile);
     const patchHint =
         providerInfo.patchHint ??
         'This dependency has local patches applied. When upgrading, check if the patches are still needed or should be removed.';
@@ -209,7 +211,8 @@ export function buildGroupIssueDescription({
             `No provider info for ecosystem "${firstDep.ecosystem}" in group "${groupName}"`,
         );
     }
-    const { installCommand, supportsCatalog, catalogFile } = groupProviderInfo;
+    const { installCommand, supportsCatalog } = groupProviderInfo;
+    const catalogFile = normalizeCatalogFile(groupProviderInfo.catalogFile);
     const updateInstructions =
         groupProviderInfo.updateInstructions ??
         `Update each dependency's version in the appropriate config file, then run \`${installCommand}\`.`;
diff --git a/src/github-issues/templates/group-description.hbs b/src/github-issues/templates/group-description.hbs
index 0de9f23..97e8749 100644
--- a/src/github-issues/templates/group-description.hbs
+++ b/src/github-issues/templates/group-description.hbs
@@ -38,7 +38,7 @@ This issue tracks updates for the **{{groupName}}** dependency group.
 ## How to Update
 
 {{#if supportsCatalog}}
-Update each dependency in the `{{catalogFile}}` catalog (if applicable) or individual package.json files:
+Update each dependency in the {{#if catalogFile}}`{{catalogFile}}` catalog{{else}}catalog{{/if}} (if applicable) or individual package.json files:
 
 ```yaml
 catalog:
diff --git a/src/github-issues/templates/issue-description.hbs b/src/github-issues/templates/issue-description.hbs
index e98e0bd..b2d79f0 100644
--- a/src/github-issues/templates/issue-description.hbs
+++ b/src/github-issues/templates/issue-description.hbs
@@ -34,7 +34,7 @@
 
 {{#if supportsCatalog}}
 {{#if inCatalog}}
-This dependency is managed in the catalog. Edit `{{catalogFile}}`:
+{{#if catalogFile}}This dependency is managed in the catalog. Edit `{{catalogFile}}`:{{else}}This dependency is managed in the catalog. Update it in the catalog:{{/if}}
 
 ```yaml
 catalog:
@@ -46,7 +46,7 @@ Then, run `{{installCommand}}` to update the lockfile.
 {{#if shouldRecommendCatalog}}
 This dependency is used by {{usedByCount}} packages. Consider adding it to the catalog:
 
-1. **Add to catalog** - Edit `{{catalogFile}}`:
+1. **Add to catalog** - {{#if catalogFile}}Edit `{{catalogFile}}`:{{else}}Add it to the catalog:{{/if}}
 
 ```yaml
 catalog:
diff --git a/src/linear/issueDescriptions.test.ts b/src/linear/issueDescriptions.test.ts
index e7ed60c..2e8da29 100644
--- a/src/linear/issueDescriptions.test.ts
+++ b/src/linear/issueDescriptions.test.ts
@@ -296,6 +296,38 @@ describe('buildIssueDescription', () => {
         expect(result).toContain('  test-pkg: 2.0.0');
     });
 
+    it('avoids a broken catalog file reference when catalogFile is missing', () => {
+        const pkg = makeDependency();
+        const store = makeStore(pkg);
+        const { catalogFile: _catalogFile, ...providerInfoWithoutCatalogFile } = npmProviderInfo;
+        const result = buildIssueDescription({
+            dep: pkg,
+            store: store,
+            minVersion: '1.1.0',
+            effectiveLatestVersion: '2.0.0',
+            getDetailUrl: testGetDetailUrl,
+            providerInfo: providerInfoWithoutCatalogFile,
+        });
+        expect(result).toContain('managed in the catalog');
+        expect(result).not.toContain('Edit ``');
+        expect(result).not.toContain('undefined');
+    });
+
+    it('treats a literal "undefined" catalogFile as missing', () => {
+        const pkg = makeDependency();
+        const store = makeStore(pkg);
+        const result = buildIssueDescription({
+            dep: pkg,
+            store: store,
+            minVersion: '1.1.0',
+            effectiveLatestVersion: '2.0.0',
+            getDetailUrl: testGetDetailUrl,
+            providerInfo: { ...npmProviderInfo, catalogFile: 'undefined' },
+        });
+        expect(result).toContain('managed in the catalog');
+        expect(result).not.toContain('Edit `undefined`');
+    });
+
     it('shows non-catalog How to Update for single consumer', () => {
         const pkg = makeDependency({
             versions: [makeVersion({ inCatalog: false, usedBy: ['@app/web'] })],
@@ -702,6 +734,28 @@ describe('buildGroupIssueDescription', () => {
         expect(result).toContain('react: 2.0.0');
     });
 
+    it('avoids a broken catalog file reference in groups when catalogFile is missing', () => {
+        const group: OutdatedGroup = {
+            groupName: 'test-group',
+            dependencies: [makeDependency({ name: 'react' })],
+            teamId: 'team-123',
+            policy: { type: 'dueDate' },
+            worstCompliance: { updateType: 'major', daysOverdue: 0, thresholdDays: 360 },
+        };
+
+        const store = makeGroupStore(group);
+        const { catalogFile: _catalogFile, ...providerInfoWithoutCatalogFile } = npmProviderInfo;
+        const result = buildGroupIssueDescription({
+            group: group,
+            store: store,
+            getDetailUrl: testGetDetailUrl,
+            providerInfoMap: new Map([['npm', providerInfoWithoutCatalogFile]]),
+        });
+        expect(result).toContain('Update each dependency in the catalog');
+        expect(result).not.toContain('`` catalog');
+        expect(result).not.toContain('undefined');
+    });
+
     it('quotes scoped package names in group catalog YAML', () => {
         const group: OutdatedGroup = {
             groupName: 'scoped-group',
diff --git a/src/linear/issueDescriptions.ts b/src/linear/issueDescriptions.ts
index ebcce6d..5b70938 100644
--- a/src/linear/issueDescriptions.ts
+++ b/src/linear/issueDescriptions.ts
@@ -6,6 +6,7 @@ import {
     findFirstVersionOfType,
     formatBytes,
     formatSizeChange,
+    normalizeCatalogFile,
     resolveUrlPatterns,
 } from '../core/index';
 import { helpers } from './templates/helpers';
@@ -111,7 +112,8 @@ export function buildIssueDescription({
         };
     });
 
-    const { installCommand, supportsCatalog, catalogFile } = providerInfo;
+    const { installCommand, supportsCatalog } = providerInfo;
+    const catalogFile = normalizeCatalogFile(providerInfo.catalogFile);
     const patchHint =
         providerInfo.patchHint ??
         'This dependency has local patches applied. When upgrading, check if the patches are still needed or should be removed.';
@@ -204,7 +206,8 @@ export function buildGroupIssueDescription({
             `No provider info for ecosystem "${firstDep.ecosystem}" in group "${groupName}"`,
         );
     }
-    const { installCommand, supportsCatalog, catalogFile } = groupProviderInfo;
+    const { installCommand, supportsCatalog } = groupProviderInfo;
+    const catalogFile = normalizeCatalogFile(groupProviderInfo.catalogFile);
     const updateInstructions =
         groupProviderInfo.updateInstructions ??
         `Update each dependency's version in the appropriate config file, then run \`${installCommand}\`.`;
diff --git a/src/linear/templates/group-description.hbs b/src/linear/templates/group-description.hbs
index 012dfa8..4a661c7 100644
--- a/src/linear/templates/group-description.hbs
+++ b/src/linear/templates/group-description.hbs
@@ -35,7 +35,7 @@ This issue tracks updates for the **{{groupName}}** dependency group.
 ## How to Update
 
 {{#if supportsCatalog}}
-Update each dependency in the `{{catalogFile}}` catalog (if applicable) or individual package.json files:
+Update each dependency in the {{#if catalogFile}}`{{catalogFile}}` catalog{{else}}catalog{{/if}} (if applicable) or individual package.json files:
 
 ```yaml
 catalog:
diff --git a/src/linear/templates/issue-description.hbs b/src/linear/templates/issue-description.hbs
index 46e15e9..a15f582 100644
--- a/src/linear/templates/issue-description.hbs
+++ b/src/linear/templates/issue-description.hbs
@@ -31,7 +31,7 @@
 
 {{#if supportsCatalog}}
 {{#if inCatalog}}
-This dependency is managed in the catalog. Edit `{{catalogFile}}`:
+{{#if catalogFile}}This dependency is managed in the catalog. Edit `{{catalogFile}}`:{{else}}This dependency is managed in the catalog. Update it in the catalog:{{/if}}
 
 ```yaml
 catalog:
@@ -43,7 +43,7 @@ Then, run `{{installCommand}}` to update the lockfile.
 {{#if shouldRecommendCatalog}}
 This dependency is used by {{usedByCount}} packages. Consider adding it to the catalog:
 
-1. **Add to catalog** - Edit `{{catalogFile}}`:
+1. **Add to catalog** - {{#if catalogFile}}Edit `{{catalogFile}}`:{{else}}Add it to the catalog:{{/if}}
 
 ```yaml
 catalog: