CVE WatchSep 10, 2026

CVE-2026-89011

isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server o

CVSS

7.1

High

EPSS

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KEV

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Exploit Today

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0-100

Published: Sep 10, 2026 · Last modified: Sep 10, 2026 · CWE-1321

EPSS · 30d

Not enough EPSS history yet.

Technical description

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.

Official references

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