CVE-2023-47627 | Request smuggling in aiohttp

Exp

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. The HTTP parser in AIOHTTP has numerous problems with header parsing, which could lead to request smuggling. This parser is only used when AIOHTTP_NO_EXTENSIONS is enabled (or not using a prebuilt wheel). These bugs have been addressed in commit `d5c12ba89` which has been included in release version 3.8.6. Users are advised to upgrade. There are no known workarounds for these issues.

Published: 2023-11-14 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-47627 is rated Exploit Available (55.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.85%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-47627

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-47627

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.24% 0.85% +0.61%
2 2026-04-19 0.26% 0.24% -0.02%
3 2025-12-28 — 0.26% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-47627

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-47627

GitHub Security Advisory for CVE-2023-47627

GHSA-gfw2-4jvh-wgfg · Severity: medium · Ecosystem: pip — AIOHTTP has problems in HTTP parser (the python one, not llhttp)

OS Trackers for CVE-2023-47627

vendor priority summary link
debian not yet assigned CVE-2023-47627 not yet assigned priority: Debian including 1 source packages (python-aiohttp), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2023-47627
redhat medium — https://access.redhat.com/security/cve/CVE-2023-47627
suse medium CVE-2023-47627 severity moderate: SUSE including 10 source package names (python-aiohttp, python-aiohttp-doc, …), 83 product×package rows across 68 product lines (Image SLES15-SP4-BYOS-Azure, Image SLES15-SP4-HPC-BYOS-Azure, … (68 product lines)): Fixed 63, Will Not Fix 20. https://www.suse.com/security/cve/CVE-2023-47627/
ubuntu medium CVE-2023-47627 medium priority: Ubuntu including 1 source packages (python-aiohttp), 12 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 5, ignored 4, released 3. https://ubuntu.com/security/CVE-2023-47627

Affected software / configurations for CVE-2023-47627

Vendor Product Version Raw CPE
aiohttp aiohttp < 3.8.6 cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*

References for CVE-2023-47627

cvelogic Threat Intelligence