Malicious PDF — malware analysis report

Static analysis result for SHA-256 c353293e0243f523…

MALICIOUS

PDF

76.3 KB Created: 2021-03-15 03:56:21 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8e7a54c371d889ab7013df89a2191afb SHA-1: 16a0d495f207d63c99dedfd319ab7eab4133d0fa SHA-256: c353293e0243f523776d2d29a94b9c35d04b7a9061949712ebdec1743ebc31c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many of which are SEO-optimized and point to potentially malicious domains, as indicated by the 'PDF_SEO_LINK_FARM' heuristic. The ML classifier and ClamAV also flagged this file as malicious, specifically as a phishing or trojan PDF. The document body, though heavily obfuscated, appears to be related to 'Comptia cysa exam pdf', suggesting a lure for users searching for exam materials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9819

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://jumiwimov.ru/award?keyword=comptia+cysa+exam+pdf
    • https://zadopuvaja.weebly.com/uploads/1/3/4/8/134892734/8cc38042ab46c.pdf
    • http://heliusdesign.ru/20806525341n4987.pdf
    • https://xidoferowugefu.weebly.com/uploads/1/3/4/3/134348033/9416643.pdf
    • http://feelslike35.com/mununavenxxk.pdf
    • https://memetunariva.weebly.com/uploads/1/3/1/4/131454345/0824333728c9.pdf
    • https://boripate.weebly.com/uploads/1/3/4/5/134590871/fc9fc8e14122e43.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/f7e49e25-1cc8-4a93-9ea5-c467de6a7191/14661198242.pdf
    • http://sumoxajavagal.rf.gd/left_bundle_branch_block_treatment.pdf
    • https://s3.amazonaws.com/senodiw/calculate_time_based_on_file_size.pdf
    • http://pafewanofa.epizy.com/73876601478.pdf
    • https://uploads.strikinglycdn.com/files/7e3b3634-8da1-427e-b68f-d6383a7dd8de/rulasotamanupalejekij.pdf
    • https://s3.amazonaws.com/jebokizez/is_s9_plus_discontinued.pdf
    • https://uploads.strikinglycdn.com/files/f241e67d-40f3-4ae6-8e71-96d5b4b5f652/fujubebekekezuxurag.pdf
    • https://s3.amazonaws.com/nutanigonu/wapizuriwamabena.pdf
    • https://uploads.strikinglycdn.com/files/a14f06d3-76bc-4010-8ea0-668d1b807671/48489300736.pdf
    • http://zogaxemajov.epizy.com/combat_pistol_training_near_me.pdf
    • https://s3.amazonaws.com/xasovewipeje/matlab_rectangular_waveguide.pdf
    • https://s3.amazonaws.com/sewamos/penafututuxa.pdf
    • https://uploads.strikinglycdn.com/files/ef7d6150-b3e4-4555-80e6-e20ffba0f7d3/7225217723.pdf
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f56c.bin
39844e06dd85903e262cf177a93bbdc6b7b2a71ea57e98ac48fc490e9e936269
pdf-font-stream PDF embedded font (sfnt) at offset 0xF56C 5248 bytes
font_01_sfnt_off00010741.bin
06b2ad67d7bee6ebfa91a0c8901930487e34719dda73d415cc10fee6239bff8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10741 12604 bytes