CVE-2021-45386Public exploit

Local utility crash via crafted IPv6 capture

Published Feb 11, 2022 · Updated Aug 4, 2024

Reachable assertion in tcpprep in tcpreplay 4.3.4 allows local users to crash the utility by supplying a crafted IPv6 PCAP file. While tcpprep builds its address tree, add_tree_ipv6() applies a fatal equality assertion to packet-derived IPv6 address data instead of handling a mismatch. A user must run tcpprep on the crafted capture; the assertion raises SIGABRT and terminates that process without reported data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in tcpprep in tcpreplay 4.3.4 allows local users to crash the utility by supplying a crafted IPv6 PCAP file. While tcpprep builds its address tree, add_tree_ipv6() applies a fatal equality assertion to packet-derived IPv6 address data instead of handling a mismatch. A user must run tcpprep on the crafted capture; the assertion raises SIGABRT and terminates that process without reported data disclosure or modification.

The record

CVE
CVE-2021-45386
Published
Feb 11, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-617, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 11, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
4.3NVDAV:N/AC:M/Au:N/C:N/I:N/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-617Reachable Assertion
T1204.002User Execution Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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