CVE-2021-29155

lowpriority · track · 32EPSS 0.011 · 65 %ileexploit · PoCDEEURUUS
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
1 exploit · PoC
Likely / severe?
1.07% (65th) EPSS
CVSS 2.1 · low
Is it mine?
27 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

An issue was discovered in the Linux kernel through 5.11.x. kernel/bpf/verifier.c performs undesirable out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory. Specifically, for sequences of pointer arithmetic operations, the pointer modification performed by the first operation is not correctly accounted for when restricting subsequent operations.

01

cvss

Technical severity, 0–10. One row per scoring source.

5.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 2.1–5.5

v2.02.1lowAV:L/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 2.9
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 1.8 · impact 3.6
v3.15.5mediumAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · FSTEC (BDU) RU
v3.15.2mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:Psecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125USprimaryCWE-125US
03

exploits (1)

Public proof-of-concept and weaponised exploit code.

04

affected products (27)

Products and version ranges known to be affected.

showing 20 of 27
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2022-2071Linux Kernel: Mehrere SchwachstellenDeutsch2021-04-18csaf · cert_bundDE

    Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um seine Privilegien zu erhöhen, Sicherheitsvorkehrungen zu umgehen oder Informationen offenzulegen.

  • PUB-A-1863379182021-10-01vendor · osvUS

    In several functions of verifier.c, there is a possible way to disclose kernel memory due to side channel information disclosure. This could lead to local information disclosure with System execution privileges needed. User interaction is not needed for exploitation.

06

also known as (5)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bduosvcert_bundNVDCVE.orgMITRE
published 2021-04-20modified 2026-06-17
09

references (53)

External citations — patches, advisories, analysis.

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