CVE-2021-40330Public exploitNetwork attack vector

Cross-protocol requests via newline-bearing repository paths

Published Aug 31, 2021 · Updated Aug 4, 2024

Request forgery in Git before 2.30.1 allows remote attackers to trigger cross-protocol requests through crafted git:// URLs. The git_connect_git function in connect.c copies newline-bearing host or repository-path input into the initial Git protocol request, so newline-oriented services such as HTTP parse the injected suffix as a separate request. The target must process a malicious git:// URL, including through a submodule or automated clone; the resulting request originates from the target and can reach services on arbitrary ports, while SSH and local transports are unaffected.

CVSS severity7.5
High
EPSS probability2.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Request forgery in Git before 2.30.1 allows remote attackers to trigger cross-protocol requests through crafted git:// URLs. The git_connect_git function in connect.c copies newline-bearing host or repository-path input into the initial Git protocol request, so newline-oriented services such as HTTP parse the injected suffix as a separate request. The target must process a malicious git:// URL, including through a submodule or automated clone; the resulting request originates from the target and can reach services on arbitrary ports, while SSH and local transports are unaffected.

The record

CVE
CVE-2021-40330
Published
Aug 31, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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