VulnerabilityPublished 23 Oct 2026Updated 26 Oct 2026

CVE-2026-114603: OpenTelemetry Python · Unbounded tracestate parsing in opentelemetry-api

Affects scoutsuiteSource GCVE Database

Authoritative record:CVE-2026-114603· Medium 5.3

Not known to be exploited · CVSS 5.3 Medium : upgrade to 5.14.0_18 when convenient.

Data as of 26 Oct 2026, 19:00 UTC

CVSS 3.1 base score

5.3Medium

How severe the flaw is on the 0–10 CVSS scale.

Patch: Available – fixed in 5.14.0_18

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 22 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade scoutsuite to 5.14.0_18.

Affected software

Product	Affected	Fixed in
Homebrewscoutsuite`pkg:brew/scoutsuite`Other threats	Affected >=5.14.0_1 <5.14.0_18	Fixed in 5.14.0_18

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available in OpenTelemetry Python API version 5.14.0_18. Users should upgrade to this version or later to resolve the vulnerability. Until upgraded, servers may mitigate risk by enforcing strict header size limits at the HTTP server or proxy level to reject oversized tracestate headers. Note that some HTTP servers like gunicorn and uvicorn already reject headers above certain sizes, but others like waitress and uvicorn with httptools may accept very large headers. Applying such limits can reduce exposure to this denial-of-service vector.

Description

A regular expression used in the OpenTelemetry Python API's TraceState.from_header method causes quadratic CPU time complexity when parsing specially crafted tracestate headers with long runs of spaces or tabs. This can lead to denial of service by blocking the handling worker for several seconds on a single unauthenticated request. The issue affects versions from 1.0.0 through at least v1.45.0 and is fixed in version 5.14.0_18.

Impact

An attacker can send a single unauthenticated request with a specially crafted tracestate header containing approximately 100 KB of spaces or tabs, causing the server to spend 6 to 12 seconds processing the header. This results in denial of service by blocking the handling worker and delaying other connections in asyncio-based servers. The vulnerability does not affect confidentiality or integrity but impacts availability.

Summary

The OpenTelemetry Python API's TraceState.from_header method uses a regular expression to split the W3C tracestate header that begins with an unbounded optional whitespace pattern. When parsing a tracestate header containing a long sequence of spaces or tabs without commas, the regex engine exhibits O(N²) CPU complexity due to excessive backtracking. This causes the parsing operation to consume significant CPU time, blocking the server's asyncio event loop and delaying processing of other connections. The vulnerability exists in all versions from 1.0.0 through at least v1.45.0 and is reachable via default propagators used in server instrumentation. The sibling baggage propagator implements a length check that is missing for tracestate headers. The issue is fixed in version 5.14.0_18.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 19:00 UTC

Technical details

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