Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 0.74% for the current model date.
BlackTreeCVE IntelligenceVinchin · Backup & Recovery 9.0
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Fix not verifiedVinchin Backup & Recovery through 9.0.0.86562 contains a stack buffer overflow vulnerability in the ModuleHandShake function of the agentlink_server service that allows unauthenticated remote attackers to overwrite the saved return address by supplying an oversized _listen_uuid field that is measured via strlen() and copied without bounds checking into a fixed-length stack buffer using strcpy(). Attackers can send a crafted request with a malicious _listen_uuid value to corrupt the stack and achieve process crash or potential control flow hijack without requiring authentication.
Vinchin Backup & Recovery through 9.0.0.86562 contains a stack buffer overflow vulnerability in the ModuleHandShake function of the agentlink_server service that allows unauthenticated remote attackers to overwrite the saved return address by supplying an oversized _listen_uuid field that is measured via strlen() and copied without bounds checking into a fixed-length stack buffer using strcpy(). Attackers can send a crafted request with a malicious _listen_uuid value to corrupt the stack and achieve process crash or potential control flow hijack without requiring authentication.
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.
Vinchin Backup & Recovery through 9.0.0.86562 contains a stack buffer overflow vulnerability in the ModuleHandShake function of the agentlink_server service that allows unauthenticated remote attackers to overwrite the saved return address by supplying an oversized _listen_uuid field that is measured via strlen() and copied without bounds checking into a fixed-length stack buffer using strcpy(). Attackers can send a crafted request with a malicious _listen_uuid value to corrupt the stack and achieve process crash or potential control flow hijack without requiring authentication.
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
CWE-121: Stack-based Buffer Overflow. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:NCommon Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
Operational remediation based on structured source evidence.
Published 9 Jul 2026 · Last source change 14 Aug 2026, 16:50 UTC · CWE-121 · Stack-based Buffer Overflow
Core structured fields are present and their contributing authorities are shown above.
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.