Security readout for executives and security teams
Plain-English summary
SimpleX Chat versions before 6.5 can reportedly be compromised merely by receiving a malicious text message. No user click is required. Successful exploitation could let an attacker run commands as the application, potentially exposing messages or other accessible data, altering information, and disrupting service.
Executive priority
Treat this as an immediate remediation priority because compromise reportedly requires only message delivery and can affect data confidentiality, integrity, and availability. Confirm organizational use of SimpleX Chat, upgrade pre-6.5 installations promptly, and investigate exposed endpoints for abnormal process activity.
Technical view
CVE-2026-52103 is a CWE-94 code-injection flaw in SimpleX Chat’s /Terminal/Notification.hs component. A crafted text message can trigger arbitrary command execution. The CVSS 3.1 score is 9.8: network-accessible, low complexity, no privileges or interaction required, with high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to SimpleX Chat installations earlier than version 6.5 that can receive attacker-controlled text messages. The bundle does not identify affected operating systems, packaging variants, CPEs, or whether every pre-6.5 build contains the vulnerable component.
Exploitation context
The supplied sources describe zero-click remote exploitation, but provide no evidence of active exploitation. The CVE is not listed as KEV in the bundle, and no public indicators of compromise are supplied.
Researcher notes
The record’s structured affected-product fields are unspecified, while its description explicitly names SimpleX Chat before 6.5. Assessment therefore relies on that description and the referenced disclosure. Platform scope, vulnerable version floor, root cause details, observed attacks, and authoritative indicators of compromise remain incomplete in the supplied evidence.
Mitigation direction
- Upgrade affected SimpleX Chat installations to version 6.5 or a newer vendor-supported release.
- Prioritize systems that receive messages from untrusted or unknown contacts.
- Follow current SimpleX Chat guidance for any additional mitigations or platform-specific updates.
- If immediate upgrading is impossible, restrict untrusted message delivery where operationally feasible.
Validation and detection
- Inventory SimpleX Chat versions and identify every installation earlier than 6.5.
- Confirm upgraded clients report version 6.5 or newer and operate normally.
- Review application and endpoint telemetry for unexpected processes launched in the application context.
- Check vendor guidance for affected platforms, release notes, and published indicators of compromise.
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-94: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-52103 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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.
SSVC decision data
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:H/I:H/A:H3.95.9CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://te.mpe.st/disclosures/20260510-simplex.htmlCVE reference, mitre
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.
Improper Control of Generation of Code ('Code Injection')
Improper Control of Generation of Code ('Code Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.