CVE-2021-34549
HIGH
7.5
CVSS Score
Published: June 29, 2021 at 11:08 AM UTC
Updated: June 17, 2026 at 03:56 AM UTC
1 product affected across 1 vendorTor
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Severity
HIGH7.5
Exploit prediction
EPSS 2%
Description
An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005. Hashing is mishandled for certain retrieval of circuit data. Consequently. an attacker can trigger the use of an attacker-chosen circuit ID to cause algorithm inefficiency.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 0.3.5.150.4.0.0 ≤ v < 0.4.4.90.4.5.0 ≤ v < 0.4.5.90.4.6.0 ≤ v < 0.4.6.5
Affected range stops below 0.3.5.15, so it looks safe — our inference, not a vendor statement
Affected range stops below 0.4.4.9, so it looks safe — our inference, not a vendor statement
Affected range stops below 0.4.5.9, so it looks safe — our inference, not a vendor statement
Affected range stops below 0.4.6.5, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (3)
x_refsource_CONFIRMRelease NotesVendor Advisory
Source: [email protected]
https://blog.torproject.org/node/2041x_refsource_MISCBroken Link
Source: [email protected]
https://gitlab.torproject.org/tpo/core/tor/-/issues/40391Vendor Advisoryx_refsource_GENTOOThird Party Advisory
Source: [email protected]
https://security.gentoo.org/glsa/202107-25CVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-400
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