rollbar vulnerable to Prototype Pollution in merge()

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.9 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS

• CVE-2025-62517: 0.39% estimated exploitation activity in the next 30 days; percentile 33.51 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact Prototype pollution vulnerability in merge(). If application code calls rollbar.configure() with untrusted input, prototype pollution is possible. Patches Fixed in 2.26.5 and 3.0.0-beta5. Workarounds Ensure that values passed to rollbar.configure() do not contain untrusted input. References Fixed in https://github.com/rollbar/rollbar.js/pull/1394 (2.26.x) and https://github.com/rollbar/rollbar.js/pull/1390 (3.x)

Published by the source

23 Oct 2025, 20:31 UTC

Last modified by the source

24 Oct 2025, 19:28 UTC

Source last checked

26 Oct 2026, 12:38 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-xcg2-9pp4-j82x

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-xcg2-9pp4-j82x

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# Patch Next advisory brief: CVE-2025-62517

Advisory: rollbar vulnerable to Prototype Pollution in merge()
IDs: CVE-2025-62517, GHSA-xcg2-9pp4-j82x
Record: https://patchnext.com/advisories/cve-2025-62517 (revision 2, source checked 26 Oct 2026, 12:38 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: rollbar 3.0.0-beta5, 2.26.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm rollbar: affected <= 2.26.4; >= 3.0.0-alpha1, <= 3.0.0-beta4; fixed in 3.0.0-beta5, 2.26.5

## Suggested inspection (read-only)
- `npm ls rollbar --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on rollbar.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-xcg2-9pp4-j82x (OSV record GHSA-xcg2-9pp4-j82x lists affected ranges: npm rollbar >=0 =3.0.0-alpha1 <3.0.0-beta5 (fixed))
- Verified: https://github.com/advisories/GHSA-xcg2-9pp4-j82x (GitHub-reviewed advisory GHSA-xcg2-9pp4-j82x lists affected ranges: npm rollbar >=0 =3.0.0-alpha1 <=3.0.0-beta4)

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