CyberSecBulletin
CVE-2023-29007NVD status: Modified

git: Improper Neutralization of Special Elements in Output Used by a Downstream Component

Published Updated By the CyberSecBulletin desk

CVE-2023-29007 is a high-severity improper neutralization of special elements in output used by a downstream component vulnerability in git, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected git versions: < 2.30.9; >= 2.31.0, < 2.31.8; >= 2.32.0, < 2.32.7, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 5.61% chance of exploitation within 30 days, which is in the top 6.96% of all scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of git you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Gitgit< 2.30.9; >= 2.31.0, < 2.31.8; >= 2.32.0, < 2.32.7; >= 2.33.0, < 2.33.8; >= 2.34.0, < 2.34.8; >= 2.35.0, < 2.35.8; >= 2.36.0, < 2.36.6; >= 2.37.0, < 2.37.7; and 3 more rangesNot stated
Fedora ProjectFedora36; 37; 38Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.0HighCNA (github.com)
CVSS 3.17.8HighNVD

Official description

Git is a revision control system. Prior to versions 2.30.9, 2.31.8, 2.32.7, 2.33.8, 2.34.8, 2.35.8, 2.36.6, 2.37.7, 2.38.5, 2.39.3, and 2.40.1, a specially crafted `.gitmodules` file with submodule URLs that are longer than 1024 characters can used to exploit a bug in `config.c::git_config_copy_or_rename_section_in_file()`. This bug can be used to inject arbitrary configuration into a user's `$GIT_DIR/config` when attempting to remove the configuration section associated with that submodule. When the attacker injects configuration values which specify executables to run (such as `core.pager`, `core.editor`, `core.sshCommand`, etc.) this can lead to a remote code execution. A fix A fix is available in versions 2.30.9, 2.31.8, 2.32.7, 2.33.8, 2.34.8, 2.35.8, 2.36.6, 2.37.7, 2.38.5, 2.39.3, and 2.40.1. As a workaround, avoid running `git submodule deinit` on untrusted repositories or without prior inspection of any submodule sections in `$GIT_DIR/config`.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Special Elements in Output Used by a Downstream Component

The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

How developers prevent this class of flaw

  • Programming languages and supporting technologies might be chosen which are not subject to these issues.
  • Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.

More Improper Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities (CWE-74)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in git

All git vulnerabilities

Recent Improper Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities

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