medium Known exploitedREV. 01
CVE-2025-55177WhatsApp — linked device sync accepts unrelated senders
WhatsApp for iOS before 2.25.21.73, WhatsApp Business for iOS 2.25.21.78 and WhatsApp for Mac 2.25.21.78 do not fully check who may send a linked device synchronisation message, so an unrelated user can make the target fetch content from any address.
Read the risk
THE VITAL STATS- CVSS score
- 5.4/ 10 CVSS v3.1
- EPSS probability
- 4% Likelihood of exploitation
- Attack complexity
- Low Conditions needed to exploit
- Known exploited
- Yes — CISA KEV
- CVE published
- 2025-08-29
- Added to KEV
- 2025-09-02
- Exploit published
- Not recorded
- Confidence
- high
- Kill chain
- initial access
- MITRE ATT&CK
- —
- Severity
- medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attacker needsThe attacker must be able to send the target a linked device synchronisation message.
Fixed inWhatsApp for iOS 2.25.21.73, WhatsApp Business for iOS 2.25.21.78, WhatsApp for Mac 2.25.21.78
Behind the card
4 REFERENCES- 01CVE recordNVD recordnvd.nist.gov
- 02CISACISA Known Exploited Vulnerabilities catalogcisa.gov
- 03Vendor advisoryfacebook.comfacebook.com
- 04Vendor advisorywhatsapp.comwhatsapp.com
Field-level provenanceTRACE THE SOURCES +
Which source supports each field, when it was retrieved, and who extracted it.
| Fields | Source | Retrieved | Extractor | Confidence |
|---|---|---|---|---|
| cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_at | nvd.nist.gov | 2026-09-24 | scrty-crds-pipeline/0.1 | high |
| exploitation.known_exploited, exploitation.kev_added | cisa.gov | 2026-09-24 | scrty-crds-pipeline/0.1 | high |
| epss | api.first.org | 2026-09-24 | scrty-crds-pipeline/0.1 | high |
| title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisites | nvd.nist.gov | 2026-09-24 | claude-code | high |
Printing history
THE RECORD- r1Initial base card
First printing. This card has not been reprinted since publication.