CVE-2026-44432

urllib3: Decompression-bomb safeguards bypassed in parts of the streaming API

HIGH
7.5
CVSS Score
Published: May 13, 2026 at 03:17 PM UTC
Updated: September 10, 2026 at 01:20 PM UTC
9 products affected across 3 vendorsURLLIB3OpenShift Container PlatformOpenShift AI

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Severity
HIGH7.5
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

urllib3 is an HTTP client library for Python. From 2.6.0 to before 2.7.0, urllib3 could decompress the whole response instead of the requested portion (1) during the second HTTPResponse.read(amt=N) call when the response was decompressed using the official Brotli library or (2) when HTTPResponse.drain_conn() was called after the response had been read and decompressed partially (compression algorithm did not matter here). These issues could cause urllib3 to fully decode a small amount of highly compressed data in a single operation. This could result in excessive resource consumption (high CPU usage and massive memory allocation for the decompressed data) on the client side. This vulnerability is fixed in 2.7.0.

Affected

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

2.6.0 ≤ v < 2.7.0
Affected range stops below 2.7.0, so it looks safe — our inference, not a vendor statement
All versions
Vendor states this is fixed in 1780356811 (unaffected)
Vendor states this is fixed in 1780356904 (unaffected)
Vendor states this is fixed in 1780356914 (unaffected)
Vendor states this is fixed in 1780356941 (unaffected)
Vendor states this is fixed in 1782352847 (unaffected)
Vendor states this is fixed in 1782352919 (unaffected)
Vendor states this is fixed in 1782352950 (unaffected)
Vendor states this is fixed in 1782353093 (unaffected)
Vendor states this is fixed in 0:2.7.0-1.el9ap (unaffected)
Vendor states this is fixed in 0:4.6.30-2.el8ap (unaffected)
Vendor states this is fixed in 0:4.6.30-2.el9ap (unaffected)
Vendor states this is fixed in 0:4.7.14-3.el9ap (unaffected)
Vendor states this is fixed in 1781028735 (unaffected)
Vendor states this is fixed in 1781102816 (unaffected)
Vendor states this is fixed in 1782650747 (unaffected)
Vendor states this is fixed in 1782761510 (unaffected)
Vendor states this is fixed in 1783921549 (unaffected)
Vendor states this is fixed in 1783923629 (unaffected)
Vendor states this is fixed in 1783969139 (unaffected)
Vendor states this is fixed in 1783973764 (unaffected)
Vendor states this is fixed in 1784050598 (unaffected)
Vendor states this is fixed in 2 (unaffected)
All versions
Vendor states this is fixed in 1782471555 (unaffected)
Vendor states this is fixed in 1782471579 (unaffected)
Vendor states this is fixed in 1782471656 (unaffected)
Vendor states this is fixed in 1782471663 (unaffected)
Vendor states this is fixed in 1782472374 (unaffected)
Vendor states this is fixed in 1782854229 (unaffected)
Vendor states this is fixed in 1782887848 (unaffected)
Vendor states this is fixed in 1782917849 (unaffected)
Vendor states this is fixed in 1782991170 (unaffected)
Vendor states this is fixed in 1783010225 (unaffected)
Vendor states this is fixed in 1783024305 (unaffected)
Vendor states this is fixed in 1783069204 (unaffected)
Vendor states this is fixed in 1783073038 (unaffected)
Vendor states this is fixed in 1783091175 (unaffected)
Vendor states this is fixed in 1783112979 (unaffected)
Vendor states this is fixed in 1783342900 (unaffected)
Vendor states this is fixed in 1783701598 (unaffected)
Vendor states this is fixed in 1783998774 (unaffected)
Vendor states this is fixed in 1783998857 (unaffected)
Vendor states this is fixed in 4 (unaffected)
v < 2.7.0
Affected range stops below 2.7.0, so it looks safe — our inference, not a vendor statement
All versions

Remediation

No guide yet

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

References (63)

x_refsource_CONFIRMMitigationVendor Advisory
Source: cverecord
https://github.com/urllib3/urllib3/security/advisories/GHSA-mf9v-mfxr-j63j
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:15862
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:20338
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:22934
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:24000
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:24009
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:24014
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:24069

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

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

CVSS

7.5HIGHredhat-SADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-409

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