Malicious PDF — malware analysis report

Static analysis result for SHA-256 19fb60d2aaadad90…

MALICIOUS

PDF

12.1 KB
MD5: f0b5a446efc6e99db4be81c80941e96e SHA-1: 53665c0cfc3ec447111b21d77199f94edb8ba38c SHA-256: 19fb60d2aaadad90a52e907c23598a3478ca6fc3879e6a4e3a3e96a36d8d012e
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1204.002 Malicious File

The PDF file contains multiple embedded JavaScript streams and triggers a critical heuristic for CVE-2007-5659 (Collab.collectEmailInfo). The analysis indicates that the embedded JavaScript is obfuscated and likely acts as a stager. This stager is designed to download and execute a second-stage payload, which is a common technique for initial access and further system compromise.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
e433c2f729539b14f15e0409a5799b8e028fcaae9ffd859f3af9be5c9af6b661
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
d97acb13e44562d2b38230ec343ab8e7d25e76658fce2555fdad7816726c63b8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12313 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
b26afb6ebe738403508f1475f4ceabcd1e9edf25ac2c87974c73c7069f19ba7b
deobfuscated-js PDF JavaScript deobfuscation pass 79878 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).