CVE-2026-53647 · threatengine.sh

Home/CVE/FOSSBilling is a free, open-source billing and client management system. In versions 0.5.3 through 0.7.2, the Guest `ser

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CVE-2026-536471

FOSSBilling is a free, open-source billing and client management system. In versions 0.5.3 through 0.7.2, the Guest `ser

FOSSBilling is a free, open-source billing and client management system. In versions 0.5.3 through 0.7.2, the Guest serviceapikey/get_info API endpoint is accessible without authentication. Any caller with a valid API key can retrieve all custom configuration parameters (custom_* fields) stored in the key's database record.

These custom fields are populated by billing administrators and can contain business-sensitive data such as pricing tiers, feature flags, rate limits, expiry overrides, or access scope data. Version 0.8.0 patches the issue. Some workarounds are available.

Administrators can avoid storing sensitive data in custom_* API key configuration fields, monitor API logs for suspicious calls to /api/guest/serviceapikey/get_info, and/or disable the Serviceapikey module if not in active use.

EPSS 0.0042

EPSS exploitation odds0.42% · top 66%

Schedule remediation

Public exploit or PoC is available
⚠ NVD has not scored this CVE yet - manual triage required (common for recent CVEs)

No Sigma yet — build one → YARA rules0

Look this up elsewhere - one-click external pivots

NVD CVE.org CISA Exploit-DB GitHub PoC VulnCheck KEV GreyNoise

▸ How to read a CVE - triage first, then detect and patch

This page is every public fact about CVE-2026-53647, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.

Triage: should I act now? Four signals, and they are not interchangeable:

CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked. EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal. CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score. Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.

How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.

Then what - two workflows:

Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits. PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.

Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).

⚠

Exploitation evidence

1 of 7 sources

Corroboration score 8/100 · emerging. This counts how many independent sources have exploitation evidence, and separates two different things: confirmed in-the-wild use (CISA KEV, Microsoft MSRC, ransomware activity) from exploit / PoC availability (Metasploit, ExploitDB, Nuclei, public PoCs). A template or PoC existing means an attack is possible and easy - it is not, on its own, proof the CVE is being exploited in the wild.

Exploit / PoC available

public PoC

↗

Exploitation momentum

2 days of EPSS

stable

Exploitation pressure is steady. This reads the direction and speed of EPSS over time, which can move before EPSS itself peaks or before CISA lists it.

Window

EPSS 0.004 → 0.004 peak 0.004 velocity +0.000

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Severity & exploitation scoring

EPSS exploitation probability

0.42%

Top 66%odds of exploitation in the next 30 days

CVSS metric silhouette

No structured CVSS vector for this CVE. Older entries often have only a numeric base score - the metric breakdown radar requires a full AV:_/AC:_/... vector string published by NVD.

SSVC triage · cisa-vulnrichment

Exploitation

none

Automatable

Tech impact

partial

Attack path

Full kill chain

→

⚠

Public Exploits & PoCs

These PoC and exploit links come from public sources and are not verified to be safe or functional. Review the code before running anything, and treat unverified entries as untrusted. Signed-in users mark whether it works, rate 1-10, and can report malware with a required reason that becomes a public comment.

poc 7megaumka7/FOSKiller (nomi-sec)↗ date unknown

Works? no reports yet

Rating -

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ATT&CK techniques

Techniques this CVE enables. Pills with a solid outline are high confidence - named directly in ATT&CK or Nuclei, or human-curated by CTID; the rest are inferred from the weakness type using MITRE's CVE Mapping Methodology and the CWE → CAPEC chain. Broad, generic-weakness guesses are filtered out. A small N× marks a technique that N independent sources agree on.

▤ Build a SIEM detection for these techniques

▤

CAPEC attack patterns

Attack patterns this CVE enables - the bridge from weakness to ATT&CK technique.

CAPEC-CAPEC-116 · Excavation CAPEC-CAPEC-12 · Choosing Message Identifier CAPEC-CAPEC-13 · Subverting Environment Variable Values CAPEC-CAPEC-166 · Force the System to Reset Values CAPEC-CAPEC-169 · Footprinting CAPEC-CAPEC-216 · Communication Channel Manipulation CAPEC-CAPEC-22 · Exploiting Trust in Client CAPEC-CAPEC-224 · Fingerprinting CAPEC-CAPEC-285 · ICMP Echo Request Ping CAPEC-CAPEC-287 · TCP SYN Scan CAPEC-CAPEC-290 · Enumerate Mail Exchange (MX) Records CAPEC-CAPEC-291 · DNS Zone Transfers

⬡

Weakness Classification

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-306Missing Authentication for Critical Function
CWE-862Missing Authorization

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Related CVEs

CVEs linked to this one by a shared weakness (CWE) or affected product - joins on data already in the engine, with the reason shown per row.

CVE-1999-0059 IRIX fam service allows an attacker to obtain a list of all files on the server. same CWE-200 HIGH CVE-1999-0524 ICMP information such as (1) netmask and (2) timestamp is allowed from arbitrary... same CWE-200 MEDIUM CVE-1999-1136 Vulnerability in Predictive on HP-UX 11.0 and earlier, and MPE/iX 5.5 and earlie... same CWE-200 CVE-1999-0453 An attacker can identify a CISCO device by sending a SYN packet to port 1999, wh... same CWE-200 CVE-2002-1810 D-Link DWL-900AP+ Access Point 2.1 and 2.2 allows remote attackers to access the... same CWE-306 HIGH CVE-2004-0213 Utility Manager in Windows 2000 launches winhlp32.exe while Utility Manager is r... 4 same CWE-306 HIGH CVE-2006-0061 xlockmore 5.13 and 5.22 segfaults when using libpam-opensc and returns the under... same CWE-306 CRITICAL CVE-2006-0062 xlockmore 5.13 allows potential xlock bypass when FVWM switches to the same virt... same CWE-306 CRITICAL

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References & Sources

Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.

https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-737q-9gpr-6mpq