MyBooks: Remote Code Execution via SOCIAL_AUTH Key Name Injection in Python Config File

published 2026-08-19 2 mo ago modified 2026-09-09 1 mo ago also EUVD-2026-62486

cvss: 9.4; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits: 0; none known

MyBooks is an enhanced and easy-to-use personal ebook management web server also known as Talebook. In 3.41.2 and earlier, the AdminSettings.post handler in webserver/handlers/admin.py accepts SOCIAL_AUTH key names without validating quotes or newline characters, and SettingsLoader.dumpfile in webserver/loader.py concatenates those names into the generated Python source file auto.py without escaping them. An administrator can submit a crafted SOCIAL_AUTH key name that closes the settings dictionary and injects arbitrary Python statements. The application later executes those statements because SettingsLoader.loadfile imports auto.py as a module, and setting autoreload to true invokes restart_async so a process supervisor restarts the service and triggers the import. Successful exploitation executes commands with the privileges of the application service account and can disclose data, modify files, establish persistence, or disrupt the service. Related authorization and registration vulnerabilities can reduce the effective privilege requirement in a chained attack, but the standalone vulnerability requires administrator access. This issue is fixed in version 3.42.0.

Patch / fix

links 2

github.com/PoxenStudio/mybooks@a1780c9 commit
github.com/PoxenStudio/mybooks/releases/tag/3.42.0 release

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 2 mo ago (2026-08-19)

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.4	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CNA	4.0	9.4	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

PoxenStudio talebook

Classification

Weakness

CWE-94 Improper Control of Generation of Code
CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

Sources

CVE List CVE-2026-45272
NVD CVE-2026-45272

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary