Cyber Resilience

CVE-2021-25900

CriticalPublic PoC

Published: 26 January 2021

Published
26 January 2021
Modified
21 November 2024
KEV Added
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Patch
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CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0053 67.8th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-25900 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Servo Smallvec. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 32.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

An issue was discovered in the smallvec crate before 0.6.14 and 1.x before 1.6.1 for Rust. There is a heap-based buffer overflow in SmallVec::insert_many.

CWE(s)
CWE-787

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

servo
smallvec
0.6.3 — 0.6.14 · 1.0.0 — 1.6.1

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

References