CVE-2026-89011
isomorphic-git < 1.42.0 Prototype Pollution via getRemoteInfo
isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server operator to pollute Object.prototype by advertising crafted ref names containing 'proto' path segments during ref negotiation. Attackers controlling a Git server can advertise a specially crafted ref such as 'proto/corsProxy' to reroute all subsequent network operations through an attacker-controlled proxy, causing isomorphic-git to invoke the victim's onAuth callback and transmit credentials to the attacker when the victim calls getRemoteInfo with an attacker-supplied URL.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
7.1
isomorphic-git < 1.42.0 Prototype Pollution via getRemoteInfo
isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server operator to pollute Object.prototype by advertising crafted ref names containing 'proto' path segments during ref negotiation. Attackers controlling a Git server can advertise a specially crafted ref such as 'proto/corsProxy' to reroute all subsequent network operations through an attacker-controlled proxy, causing isomorphic-git to invoke the victim's onAuth callback and transmit credentials to the attacker when the victim calls getRemoteInfo with an attacker-supplied URL.
- Record
CVE-2026-89011- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
EUVDEUVD-2026-75710
7.1
isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server operator to pollute Object.prototype by advertising crafted ref names containing 'proto' path segments during ref negotiation. Attackers controlling a Git server can advertise a specially crafted ref such as 'proto/corsProxy' to reroute all subsequent network operations through an attacker-controlled proxy, causing isomorphic-git to invoke the victim's onAuth callback and transmit credentials to the attacker when the victim calls getRemoteInfo with an attacker-supplied URL.
- Record
EUVD-2026-75710- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
NVD
7.1
isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server operator to pollute Object.prototype by advertising crafted ref names containing 'proto' path segments during ref negotiation. Attackers controlling a Git server can advertise a specially crafted ref such as 'proto/corsProxy' to reroute all subsequent network operations through an attacker-controlled proxy, causing isomorphic-git to invoke the victim's onAuth callback and transmit credentials to the attacker when the victim calls getRemoteInfo with an attacker-supplied URL.
- Record
CVE-2026-89011- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSV
7.1
isomorphic-git < 1.42.0 Prototype Pollution via getRemoteInfo
isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server operator to pollute Object.prototype by advertising crafted ref names containing 'proto' path segments during ref negotiation. Attackers controlling a Git server can advertise a specially crafted ref such as 'proto/corsProxy' to reroute all subsequent network operations through an attacker-controlled proxy, causing isomorphic-git to invoke the victim's onAuth callback and transmit credentials to the attacker when the victim calls getRemoteInfo with an attacker-supplied URL.
- Record
CVE-2026-89011- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-89011 is a high vulnerability (CVSS 7.1) in Isomorphic-git, published September 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.44%, the 38th percentile. No source names a fixed version.
References
github.com/isomorphic-git/isomorphic-git/security/advisories/GHSA-83vg-jxvh-fx76
github.com/isomorphic-git/isomorphic-git/releases/tag/v1.42.0
github.com/isomorphic-git/isomorphic-git/pull/2426
github.com/isomorphic-git/isomorphic-git/commit/b3db111885230bac9a648e0a2312c65ca66f76eb
vulncheck.com/advisories/isomorphic-git-prototype-pollution-via-getremoteinfo
github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89011.json
nvd.nist.gov/vuln/detail/CVE-2026-89011
github.com/isomorphic-git/isomorphic-git