6.5

CVE-2021-3671: debian debian_linux NULL Pointer Dereference

Modified
AliasesALPINE-CVE-2021-3671MGASA-2021-0543UBUNTU-CVE-2021-3671
Published 12-10-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-3671 is a medium (CVSS 6.5) NULL Pointer Dereference vulnerability in debian debian_linux. EPSS estimates a 2.12% chance of exploitation in the next 30 days, higher than 81.8% of scored vulnerabilities.

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
2.12%
0%100%
Low · -0.06 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 8 · Related 5
DLA-3206-1DSA-5287-1MGASA-2022-0468OPENSUSE-SU-2023:0019-1OPENSUSE-SU-2023:0020-1USN-5142-1

Timeline

  1. 12-10-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

A null pointer de-reference was found in the way samba kerberos server handled missing sname in TGS-REQ (Ticket Granting Server - Request). An authenticated user could use this flaw to crash the samba server.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

2.12%

Chance of exploitation in the next 30 days

Percentile

82%

Versus all other CVEs

30-day change

Decrease -0.06 pp

From 2.18% 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

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

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

Debian3 products
  • heimdal< 7.7.0+dfsg-3
  • samba< 2:4.13.13+dfsg-1
  • debian_linuxEOL10.0 | 11.0
Netapp3 products
Alpine2 products
  • heimdal< 7.7.1-r0
  • samba≥ 4.14.0, < 4.14.8-r0 | ≥ 4.14.0, < 4.15.0-r0
Ubuntu2 products
  • heimdal< 1.6~git20131207+dfsg-1ubuntu1.2+esm1 | < 1.7~git20150920+dfsg-4ubuntu1.16.04.1+esm1 | < 7.5.0+dfsg-1ubuntu0.1 | < 7.7.0+dfsg-1ubuntu1.1
  • sambaAll versions (No fix recorded) | < 2:4.7.6+dfsg~ubuntu-0ubuntu2.26 | < 2:4.13.14+dfsg-0ubuntu0.20.04.1 | < 2:4.13.14+dfsg-0ubuntu1
Mageia1 product
  • heimdal< 7.7.0-5.1.mga8
Samba1 product
  • samba< 4.13.12 | ≥ 4.14.0, < 4.14.8

6 vendors · 12 products

References

17 links
Show all 17 references