CVE-2026-78678VulnerabilityPublished 4 Sep 2026Updated 26 Oct 2026

nbdime · GitPython: Incomplete unsafe_git_revision_options denylist omits --contents/-S, enabling arbitrary file read via

Affects nbdimeSource GCVE Database

Authoritative record:CVE-2026-78678· High 7.1

Not known to be exploited · CVSS 7.1 High : upgrade to 4.0.4_8 soon.

Data as of 26 Oct 2026, 17:28 UTC

CVSS 4.0 base score

7.1High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 4.0.4_8

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: None
Vulnerable system confidentiality: High
Vulnerable system integrity: None
Vulnerable system availability: None
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: High: There is a total loss of confidentiality, resulting in all information within the Vulnerable System being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade nbdime to 4.0.4_8.

Affected software

Product	Affected	Fixed in
Homebrewnbdime`pkg:brew/nbdime`Other threats	Affected >=1.1.0 <4.0.4_8	Fixed in 4.0.4_8

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available in GitPython version 4.0.4_8 that expands the denylist of unsafe git revision options to include '--contents' and '-S', preventing arbitrary file reads via these options. Users should upgrade to version 4.0.4_8 or later to remediate this vulnerability. No additional mitigation is required once patched.

Description

GitPython versions up to 3.1.58 have an incomplete denylist for unsafe git revision options in the Repo.blame() and Repo.blame_incremental() methods. This flaw allows an attacker to use the --contents or -S options to read arbitrary local files by injecting these options into the revision parameter, bypassing the denylist which only blocks write-related options. The file contents are then included in the blame result returned to the caller, potentially exposing sensitive information. A fix is available in version 4.0.4_8.

Impact

An attacker able to influence the revision parameter passed to Repo.blame() or Repo.blame_incremental() can read arbitrary local files on the host system with the privileges of the GitPython process. The contents of the targeted file appear in the blame output returned to the caller. This can lead to disclosure of sensitive information. There is no impact on integrity or availability. The vulnerability requires local or application-level access to control the revision argument.

Summary

The vulnerability in GitPython's Repo.blame() and Repo.blame_incremental() methods arises because the denylist for unsafe git revision options only includes the write-related options '--output' and '-o'. However, git blame also supports '--contents <file>' and '-S <file>', which cause the contents of the specified file to be included in the blame output, effectively leaking arbitrary file contents. Since these options are not on the denylist, an attacker can supply them as part of the revision argument, bypassing the safety check and causing the blame result to include the contents of any file readable by the host process. This is a local file read vulnerability with impact limited to the privileges of the process running GitPython. The issue is fixed in GitPython version 4.0.4_8.

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Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 17:28 UTC

Technical details

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