CVE-2026-77584

HIGH
8.2
CVSS Score
Published: August 20, 2026 at 08:38 PM UTC
Updated: October 18, 2026 at 08:10 PM UTC
1 product affected across 1 vendorTor

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Severity
HIGH8.2
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

Tor before 0.4.9.10 did not reject a CONFLUX_LINK cell that arrives on a circuit which already has attached streams. A malicious client could send a RELAY_COMMAND_BEGIN before the CONFLUX_LINK on the same circuit, attaching an exit stream that would later end up orphan leaving a dangling circuit back-pointer and a use-after-free (UAF) when the circuit is freed. This is TROVE-2026-025.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.4.9.100.4.8.1-alpha
Affected range stops below 0.4.9.10, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
LOW
Vector?

Quick Info

StatusANALYZED
CWE
CWE-821

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