| Name | CVE-2025-55131 |
| Description | A flaw in Node.js's buffer allocation logic can expose uninitialized memory when allocations are interrupted, when using the `vm` module with the timeout option. Under specific timing conditions, buffers allocated with `Buffer.alloc` and other `TypedArray` instances like `Uint8Array` may contain leftover data from previous operations, allowing in-process secrets like tokens or passwords to leak or causing data corruption. While exploitation typically requires precise timing or in-process code execution, it can become remotely exploitable when untrusted input influences workload and timeouts, leading to potential confidentiality and integrity impact. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DSA-6166-1, DSA-6272-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| nodejs (PTS) | bullseye | 12.22.12~dfsg-1~deb11u4 | fixed |
| bullseye (security) | 12.22.12~dfsg-1~deb11u8 | fixed | |
| bookworm | 18.20.4+dfsg-1~deb12u1 | vulnerable | |
| bookworm (security) | 18.20.4+dfsg-1~deb12u2 | fixed | |
| trixie (security), trixie | 20.19.2+dfsg-1+deb13u2 | fixed | |
| forky, sid | 24.15.0+dfsg+~cs24.12.2-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| nodejs | source | bullseye | (not affected) | |||
| nodejs | source | bookworm | 18.20.4+dfsg-1~deb12u2 | DSA-6272-1 | ||
| nodejs | source | trixie | 20.19.2+dfsg-1+deb13u1 | DSA-6166-1 | ||
| nodejs | source | (unstable) | 22.22.0+dfsg+~cs22.19.6-1 |
[bullseye] - nodejs <not-affected> (vulnerable code introduced later; no ZeroFillToggle)
https://nodejs.org/en/blog/vulnerability/december-2025-security-releases#timeout-based-race-conditions-make-uint8arraybufferalloc-non-zerofilled-cve-2025-55131---high
Fixed by: https://github.com/nodejs/node/commit/51f4de4b4a52b5b0eb2c63ecbb4126577e05f636 (v20.20.0)
Introduced by: https://github.com/nodejs/node/commit/c943cb4809d382d1816a5f435c0eacc14e750ab2 (v15.0.0)