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.
CVE-2026-102820
MEDIUMPre-NVD 6.26.2—Trending — 3 sources updated this weekElevated
EchelonGraph scoreMEDIUM confidence
This medium-severity CVE scores 6.2 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1% (2nd percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, secondary
6.2EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.1%CVSS: 6.2Exploit: Elevated riskExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 6.2
- EG Score
- 6.2MEDIUMmedium confidence
- EG Risk
- 44EG Risk 44/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity62% × 45%Exploitation40% × 40%Automatability0% × 15%CISA SSVC: Track at low or medium mission impact; Track* at high (mission-essential systems).Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 0.1%
- EPSS %ILE
- 2nd
- KEV
- Not listed
CISA SSVCTrack at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
September 29, 2026
Last Modified
September 30, 2026
Advisory Details (3)
Auto-updated Sep 29, 2026🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github_release Patch Available
v0.63.2
Patch available: Eugeny/russh v0.63.2
https://github.com/Eugeny/russh/releases/tag/v0.63.2github_commit Patch Available
commit 5d566989ebab (Eugeny/russh)
Patch available: Eugeny/russh v0.63.2 (contains commit 5d566989ebab)
https://github.com/Eugeny/russh/commit/5d566989ebabfdebfe6b33243d31765a0812260bgithub Patch Available🟡 PoC Available
Out-of-bounds read / oversized allocation in `pageant` MemoryMap::read via a malicious Pageant agent (Windows) · Advisory · Eugeny/russh · GitHub
https://github.com/Eugeny/russh/security/advisories/GHSA-g4mp-vgx3-xrvmVendor Advisories for CVE-2026-102820(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
crates.io(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| pageant | — | 0.2.3 | — |
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 12× in last 7d / 12× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-03 23:10 UTCEG score recompute
- 2026-10-03 14:25 UTCEPSS rescore
- 2026-10-02 22:34 UTCEG score recompute
- 2026-10-01 22:02 UTCEG score recompute
- 2026-10-01 19:49 UTCEPSS rescore
- 2026-09-30 21:29 UTCEG score recompute
- 2026-09-30 20:27 UTCEG score recompute
- 2026-09-30 19:52 UTCEG score recompute
- 2026-09-30 15:02 UTCEPSS rescore
- 2026-09-29 19:20 UTCEG score recompute
- 2026-09-29 18:29 UTCEG score recompute
- 2026-09-29 18:28 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-102820?
CVE-2026-102820 is a medium vulnerability published on September 29, 2026. 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…
When was CVE-2026-102820 disclosed?
CVE-2026-102820 was first published on September 29, 2026, with the most recent update on September 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-102820 actively exploited?
CVE-2026-102820 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.1% probability of exploitation in the next 30 days (2nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-102820?
CVE-2026-102820 has a CVSS base score of 6.2 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-102820?
A fix for CVE-2026-102820 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-102820 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-102820
Is Your Infrastructure Affected by CVE-2026-102820?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.