Security readout for executives and security teams
Plain-English summary
CVE-2021-41119 can make affected Wire back-end servers spend excessive CPU time parsing a specially crafted object. The practical risk is service slowdown or denial of service, not data theft or system takeover. Wire managed services were already fixed; self-hosted deployments before wire-server v2022-03-01 need attention.
Executive priority
Treat this as a moderate availability risk. It should be scheduled promptly for self-hosted Wire environments, especially business-critical or externally reachable deployments. It is not described as a data breach vulnerability in the provided sources.
Technical view
wire-server releases before v2022-03-01 are vulnerable to hash-collision behavior in JSON parsing. A crafted object can force at least quadratic parsing time, causing uncontrolled resource consumption and reduced availability. The CVSS 3.1 score is 5.3, with network reachability, low complexity, no privileges, no user interaction, and low availability impact.
Likely exposure
Exposure is limited to organizations running on-premises wire-server versions earlier than v2022-03-01. The source bundle states Wire managed services already received the fix. Environments without self-hosted Wire back-end services are unlikely to be affected by this CVE.
Exploitation context
The issue is remotely reachable and unauthenticated according to the CVSS vector, but the provided sources do not show known active exploitation and KEV is false. The described impact is denial of service through parser resource exhaustion, not confidentiality or integrity compromise.
Researcher notes
The core weakness is CWE-400 resource consumption caused by hash collision behavior during JSON parsing. Public details support impact and affected version boundaries, but the bundle does not provide exploit prevalence, detection signatures, or workaround guidance beyond upgrading.
Mitigation direction
- Upgrade on-premises wire-server to v2022-03-01 or later.
- Prioritize internet-facing or heavily used Wire back-end services.
- Do not rely on workaround controls; sources state none are known.
- Check vendor guidance before applying nonstandard compensating controls.
Validation and detection
- Inventory all on-premises wire-server deployments and recorded versions.
- Confirm no production instance runs a version earlier than v2022-03-01.
- Verify Wire managed service usage separately from self-hosted deployments.
- Review availability monitoring for unexplained parser-related service degradation.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-400: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-41119 mapping review
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Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L3.91.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/wireapp/wire-server/security/advisories/GHSA-phxv-pffh-fq2rCVE reference · x_refsource_CONFIRM
- https://cs-syd.eu/posts/2021-09-11-json-vulnerabilityCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Uncontrolled Resource Consumption
Uncontrolled Resource Consumption represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.