7.5

CVE-2021-45098: debian debian_linux

CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2021-45098DEBIAN-CVE-2021-45098
Published 16-12-2021Last modified 03-11-2025
Open JSON

Vulnerability summary

CVE-2021-45098 is a high (CVSS 7.5) vulnerability in debian debian_linux. EPSS estimates a 1.96% chance of exploitation in the next 30 days, higher than 80.1% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
40/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
1.96%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 1
DLA-4103-1

Timeline

  1. 16-12-2021
    PublishedVulnerability first disclosed.
  2. 03-11-2025
    Last modifiedVulnerability information updated.

Description

An issue was discovered in Suricata before 6.0.4. It is possible to bypass/evade any HTTP-based signature by faking an RST TCP packet with random TCP options of the md5header from the client side. After the three-way handshake, it's possible to inject an RST ACK with a random TCP md5header option. Then, the client can send an HTTP GET request with a forbidden URL. The server will ignore the RST ACK and send the response HTTP packet for the client's request. These packets will not trigger a Suricata reject action.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

1.96%

Chance of exploitation in the next 30 days

Percentile

80%

Versus all other CVEs

30-day change

+0.14 pp

From 1.82% on 21-09-2026

21-09-202621-10-2026
EPSS score
1.96%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (redmine.openinfosecfoundation.org)

    Maturity: unknown

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Debian2 products
Oisf1 product
Ubuntu1 product
  • suricataAll versions (No fix recorded)

3 vendors · 4 products

References

8 links