In Twisted Web through 19.10.0, there was an HTTP request splitting vulnerability.
In Twisted Web through 19.10.0, there was an HTTP request splitting vulnerability. When presented with two content-length headers, it ignored the first header. When the second content-length value was set to zero, the request body was interpreted as a pipelined request.
- Published
- Mar 12, 2020
- Updated
- Jun 16, 2026
- EPSS
- 4.0% · 90th percentile
- CWE
- CWE-444
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Report tools
Action score
40
Plan
Add it to your regular patch cycle.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.0%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| twisted | twisted | cpe:2.3:a:twisted:twisted |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| oracle | zfs storage appliance kit | cpe:2.3:a:oracle:zfs_storage_appliance_kit |
| oracle | solaris | cpe:2.3:o:oracle:solaris |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical ubuntu linux14.04
- canonical ubuntu linux16.04
- canonical ubuntu linux18.04
- canonical ubuntu linux19.10
- debian debian linux9.0
- fedoraproject fedora31
- fedoraproject fedora32
- oracle solaris10
- oracle solaris11
- oracle zfs storage appliance kit8.8
- twisted twistedup to 19.10.0 inclusive
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | twisted | before 18.9.0-7 | 18.9.0-7 |
| Debian:8 | twisted | before 14.0.2-3+deb8u1 | 14.0.2-3+deb8u1 |
| Debian:9 | twisted | before 16.6.0-2+deb9u1 | 16.6.0-2+deb9u1 |
| openSUSE:Tumbleweed | matrix-synapse | before 1.43.0-1.1 | 1.43.0-1.1 |
| PyPI | twisted | before 20.3.0 | 20.3.0 |
| PyPI | twisted | before 20.3.0rc1 | 20.3.0rc1 |
| Red Hat:enterprise_linux:6::client | python-twisted-web | before 0:8.2.0-6.el6_10 | 0:8.2.0-6.el6_10 |
| Red Hat:enterprise_linux:7::client | python-twisted-web | before 0:12.1.0-7.el7_8 | 0:12.1.0-7.el7_8 |
| SUSE:HPE Helion OpenStack 8 | python-Twisted | before 15.2.1-9.20.1 | 15.2.1-9.20.1 |
| SUSE:HPE Helion OpenStack 8 | python-Twisted | before 15.2.1-9.23.1 | 15.2.1-9.23.1 |
Same product
twisted: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-10109In Twisted Web through 19.10.0, there was an HTTP request splitting vulnerability.40Plan
- CVE-2024-41671twisted.web has disordered HTTP pipeline response33Monitor
- CVE-2022-24801HTTP Request Smuggling in twisted.web33Monitor
- CVE-2022-21716Buffer Overflow in Twisted31Monitor
- CVE-2014-7143Python Twisted 14.0 trustRoot is not respected in HTTP client31Monitor
- CVE-2026-42304Twisted: Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains30Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:twisted | 18.9.0-7 · Debian:12 | Package registry (OSV) |
| opensuse:matrix-synapse | 1.43.0-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| PyPI:twisted | 20.3.0 | Package registry (OSV) |
| PyPI:twisted | 20.3.0rc1 | Package registry (OSV) |
| red hat:python-twisted-web | 0:12.1.0-7.el7_8 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| suse:python-Twisted | 15.2.1-9.20.1 · SUSE:HPE Helion OpenStack 8 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
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References
- know.bishopfox.com/advisories/twisted-version-19.10.0
- lists.debian.org/debian-lts-announce/2022/02/msg00021.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6ISMZFZBWW4EV6ETJGXAYIXN3AT7GBPL/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YW3NIL7VXSGJND2Q4BSXM3CFTAFU6T7D/
- security.gentoo.org/glsa/202007-24
- usn.ubuntu.com/4308-1/
- usn.ubuntu.com/4308-2/
- www.oracle.com/security-alerts/cpuoct2020.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.