Malicious PDF — malware analysis report

Static analysis result for SHA-256 beff85a2ab0e22a0…

MALICIOUS

PDF

12.1 KB
MD5: 54d291760186ff5423b97019515abab1 SHA-1: 88f18213d1b0b48183c23b2237a38a01ff872e02 SHA-256: beff85a2ab0e22a04cabd722e178f92277215c76a573470f9ee892141932ad53
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF document contains embedded JavaScript, identified by the 'PDF_JAVASCRIPT' and 'PDF_JS' heuristics. Specifically, the 'CVE_2007_5659' and 'PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER' rules indicate that the sample leverages a known vulnerability to execute a hex-decoded JavaScript stager. This stager is responsible for downloading and executing a second-stage payload, as evidenced by the large size of the 'deobfuscated.js' artifact and the ClamAV detection 'Pdf.Exploit.Agent-36063'. The primary attack vector appears to be exploiting a PDF vulnerability to initiate a malicious script execution chain.

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 3

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
9b3839796219c9c05769ad14121cf151cc469d1b65765cbecc65f0425f3ba19e
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5218 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
e49b0c138fe56b4daed3725d3277601626ba0b8b0adb4ad7ede628fcf168160c
deobfuscated-js PDF JavaScript deobfuscation pass 80229 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).