6.5

CVE-2021-22959: debian debian_linux

Modified
AliasesALPINE-CVE-2021-22959UBUNTU-CVE-2021-22959DEBIAN-CVE-2021-22959
Published 15-11-2021Last modified 30-04-2025

Vulnerability summary

CVE-2021-22959 is a medium (CVSS 6.5) vulnerability in debian debian_linux. EPSS estimates a 3.16% chance of exploitation in the next 30 days, higher than 87.9% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Routine

Not severe (CVSS 6.5, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.1 (NVD)
EPSS score
3.16%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 23 · Related 14
DSA-5170-1MGASA-2021-0592OPENSUSE-SU-2021:1552-1OPENSUSE-SU-2021:1574-1OPENSUSE-SU-2021:3940-1OPENSUSE-SU-2021:3964-1

Timeline

  1. 15-11-2021
    PublishedVulnerability first disclosed.
  2. 30-04-2025
    Last modifiedVulnerability information updated.

Description

The parser in accepts requests with a space (SP) right after the header name before the colon. This can lead to HTTP Request Smuggling (HRS) in llhttp < v2.1.4 and < v6.0.6.

CVSS metrics

7 scores · 6 sources · 2 versions

EPSS trend

Probability

3.16%

Chance of exploitation in the next 30 days

Percentile

88%

Versus all other CVEs

30-day change

No change 0.00 pp

From 3.16% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (hackerone.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine2 products
  • nodejs< 12.22.10-r0 | < 14.18.1-r0
  • nodejs-current< 16.11.1-r0
Debian2 products
Chainguard1 product
  • ruby3.2-llhttpAll versions (No fix recorded)
Llhttp1 product
  • llhttp< 2.1.4 | ≥ 3.0.0, < 6.0.6
Nodejs1 product
  • node≥ 4.0, < 4.* | ≥ 5.0, < 5.* | ≥ 6.0, < 6.* | ≥ 7.0, < 7.* | ≥ 8.0, < 8.* | ≥ 9.0, < 9.* | ≥ 10.0, < 10.* | ≥ 11.0, < 11.* | ≥ 12.0, < 12.22.7 | ≥ 13.0, < 13.* | ≥ 14.0, < 14.18.1 | ≥ 15.0, < 15.* | ≥ 16.0, < 16.11.1
Oracle1 product
Ubuntu1 product
  • nodejs< 12.22.9~dfsg-1ubuntu3
Wolfi1 product
  • ruby3.2-llhttpAll versions (No fix recorded)

8 vendors · 10 products

References

8 links