CVE-2026-102820
MEDIUMDescription
pageant provides a [PageantStream] type that implements [AsyncRead] and [AsyncWrite] traits and can be used to talk to a running Pageant instance. Prior to pageant 0.2.3, the Windows pageant crate's pageant/src/wmmessage.rs MemoryMap::read function trusts a peer-controlled u32 response length supplied through the 8192-byte Pageant shared-memory mapping reached by AgentClient::connect_pageant. A local process that impersonates the Pageant window can make query_pageant_direct allocate up to approximately 4 GiB and copy beyond the mapped view, reliably crashing a russh client and conditionally exposing adjacent committed memory. This issue is fixed in pageant 0.2.3.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploit Intelligence
Low risk: more likely to be exploited than 2% of all known CVEs.
References
Related Vulnerabilities
Other CWE-125 (Out-of-bounds Read) vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2014-0160 | High | 7.5 | 100% | KEV | Fix |
| CVE-2025-5777 | High | 7.5 | 100% | KEV + Ransom | Fix |
| CVE-2021-4034 | High | 7.8 | 94% | KEV + Ransom | Fix |
| CVE-2020-8794 | Critical | 9.8 | 89% | - | Fix |
| CVE-2023-21769 | High | 7.5 | 89% | - | Fix |
| CVE-2023-49285 | High | 8.6 | 88% | - | Fix |
Common questions
How do I fix CVE-2026-102820?
Upgrade rust-russh on debian unstable to 0.64.1-1 or later.
Is CVE-2026-102820 being actively exploited?
Not that we know of. CVE-2026-102820 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.13% is the estimated probability that it will be exploited in the next 30 days. That is higher than 2% of all scored CVEs.
How severe is CVE-2026-102820?
CVE-2026-102820 has a CVSS v3 base score of 6.2, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-102820 affect?
Published advisories record a fix for rust-russh (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-102820
Markdown
[](https://tridentstack.com/cve/CVE-2026-102820)HTML
<a href="https://tridentstack.com/cve/CVE-2026-102820"><img src="https://tridentstack.com/cve/badge/CVE-2026-102820.svg" alt="CVE-2026-102820"></a>Check your Linux endpoints for this class of vulnerability
TridentStack Control continuously scans Linux endpoints for known vulnerabilities and deploys the fixes from the same console. 200 endpoints free forever, no credit card.
This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-09-30.