CVE-2026-48083 OpenReception: Unauthenticated POST /api/log accepts arbitrary content with CRLF injection and no size or rate limits
Unauthenticated attackers can inject arbitrary content into logs, causing log forgery, SIEM pollution, and denial of service via volume or size.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-48083?
CVE-2026-48083 is a medium-severity vulnerability in open-reception appointment-booking-software, published on 6 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.2, the `/api/log` endpoint accepts unauthenticated POST requests, applies no schema validation to the message body, writes attacker-controlled content directly into the application's stdout log, interprets newline characters as real line breaks, and enforces no size or rate limits. Three independent abuse modes follow: log injection (forge log lines that look like legitimate system events), log volume DoS (saturate the logging pipeline at sustained 100+ requests per second of small messages), and oversized-payload submission (100 KB payloads accepted; larger sizes not tested). The most operationally damaging mode is log injection. An attacker can inject lines that an operator scanning logs would mistake for real system errors, mask their own activity behind fake noise, or pollute SIEM alerting rules with crafted false positives. A line such as `[error]: injected admin error` injected from an unauthenticated source is indistinguishable from the application's own error output once written to disk. Version 1.0.2 fixes the issue.
Weakness: CWE-117
Which versions are affected by CVE-2026-48083?
How do I fix CVE-2026-48083?
No fix has been published for CVE-2026-48083 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-48083 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48083 exists.
Sources
Also known as GHSA-fw48-38r5-7ffj.