9.1

CVE-2021-41945: encode httpx Improper Input Validation

CVSS: 9.1v3.1CriticalModified
AliasesGHSA-h8pj-cxx2-jfg2PYSEC-2022-183UBUNTU-CVE-2021-41945
Published 28-04-2022Last modified 09-07-2026
Open JSON

Vulnerability summary

CVE-2021-41945 is a critical (CVSS 9.1) Improper Input Validation vulnerability in encode httpx. EPSS estimates a 2.12% chance of exploitation in the next 30 days, higher than 81.5% of scored vulnerabilities. 2 public exploits are recorded.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
2.12%
0%100%
Low · -0.06 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits2github

Timeline

  1. 28-04-2022
    PublishedVulnerability first disclosed.
  2. 09-07-2026
    Last modifiedVulnerability information updated.

Description

Encode OSS httpx < 0.23.0 is affected by improper input validation in `httpx.URL`, `httpx.Client` and some functions using `httpx.URL.copy_with`.

CVSS metrics

6 scores · 4 sources · 3 versions

EPSS trend

Probability

2.12%

Chance of exploitation in the next 30 days

Percentile

82%

Versus all other CVEs

30-day change

-0.06 pp

From 2.18% on 20-09-2026

20-09-202620-10-2026
EPSS score
2.12%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

2 found
  • githubUnverified

    4Edb76Bbd3B5Ff993Cf44F2Fbce5E571

    Maturity: poc

  • githubUnverified

    Httpx

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • httpx< 0.23.0-1
Encode1 product
Opensuse1 product
  • python-httpx&distro=openSUSE Tumbleweed< 0.28.1-2.1
PyPI1 product
  • httpx< 0.23.0 | < 0.20.0
Ubuntu1 product
  • httpxAll versions (No fix recorded)

5 vendors · 5 products

References

17 links
Show all 17 references