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PatchSiren cyber security CVE debrief

CVE-2026-48083 open-reception CVE debrief

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.

Vendor
open-reception
Product
appointment-booking-software
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-06
Original CVE updated
2026-09-08
Advisory published
2026-08-06
Advisory updated
2026-09-08

Who should care

Defenders responsible for OpenReception's appointment booking software, security teams monitoring logs and SIEM systems, and operators scanning logs for system errors should be aware of this vulnerability and take necessary actions to verify exposure and mitigate risks.

Why it matters

CVE-2026-48083 is a log injection vulnerability in OpenReception's appointment booking software prior to version 1.0.2, allowing attackers to inject fake log lines, mask activity, and pollute SIEM rules. Defenders should verify exposure, assess risks, and apply version 1.0.2 or compensating controls.

  • Log injection can lead to fake system errors, masking of attacker activity, and pollution of SIEM alerting rules with crafted false positives.
  • Log volume DoS can saturate the logging pipeline, causing performance issues.
  • Oversized-payload submission can cause issues with log processing and storage.
  • Verification of exposure and mitigation of log injection, log volume DoS, and oversized-payload submission risks is necessary.

Technical summary

The `/api/log` endpoint in OpenReception's appointment booking software prior to version 1.0.2 is vulnerable to log injection, log volume DoS, and oversized-payload submission. 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. This vulnerability allows for log injection, which can lead to fake system errors, masking of attacker activity, and pollution of SIEM alerting rules with crafted false positives. Additionally, log volume DoS can saturate the logging pipeline, causing performance issues, and oversized-payload submission can cause issues with log processing

Defensive priority

Defenders should prioritize verifying exposure of the `/api/log` endpoint, assessing log injection, log volume DoS, and oversized-payload submission risks, and applying version 1.0.2 or compensating controls.

Recommended defensive actions

  • Verify exposure of the `/api/log` endpoint
  • Assess log injection, log volume DoS, and oversized-payload submission risks
  • Apply version 1.0.2 or compensating controls
  • Monitor logs for suspicious activity
  • Implement rate limiting and schema validation for the `/api/log` endpoint

Evidence notes

The CVE record and NVD vulnerability detail page provide information on the vulnerability, including its description, CVSS score, and affected versions. The `/api/log` endpoint in OpenReception's appointment booking software prior to version 1.0.2 is vulnerable to log injection, log volume DoS, and oversized-payload submission. Evidence from the CVE Program and NVD detail page indicates that defenders should verify exposure, assess log injection, log volume DoS, and oversized-payload submission risks, and apply version 1.0.2 or mitig

Sources and references

Verified primary and authoritative sources

  • CVE-2026-48083 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-48083

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-48083 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-48083

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://github.com/open-reception/appointment-booking-software/commit/36104d21ee0b6616f1c10273ec9970a27cb56b57

    [email protected]

  • Source reference

    Unverified legacy reference

    URL: https://github.com/open-reception/appointment-booking-software/security/advisories/GHSA-fw48-38r5-7ffj

    [email protected]

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.