01 Record
CVE-2026-61534
Yayson: Prototype pollution in the Store/LegacyStore deserialization
CriticalPUBLISHEDCNA: GitHub_M
CNA base score9.1 CVSS v3.xCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
02 Description
Yayson: Prototype pollution in the Store/LegacyStore deserialization
03 Exploitation and scoring
- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.84% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 57.5% of scored records. A rank, not a probability.
- NVD base score
- 9.1 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
- NVD analysis status
- Received. NVD last modified this record on 2026-09-14.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-09-14 15:36Z1 MO AGO
- Last updated
- 2026-09-14 19:19Z1 MO AGO
- Reserved
- 2026-07-10
- Assigning CNA
- GitHub_M
- Record state
- PUBLISHED
- Severity
- Critical (CVSS 9.1)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
- Weaknesses
- CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')Variant
- Data version
- 5.2
- Document digest
- 7f25a4df9b1db206b48ccd346a0d5965e76a6a0280cd89fbbc94ac5d36928161
05 Affected products
VendorProductVersionsPlatforms