Malicious PDF — malware analysis report

Static analysis result for SHA-256 7804a8f345355a4f…

MALICIOUS

PDF

75.1 KB Created: 2020-11-17 21:37:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d1455de2f5b3f26c2689a4b5cf3743f0 SHA-1: 747174867d415d2856e13972769959498e6246d9 SHA-256: 7804a8f345355a4fc9daa564da6d4b61b48d26ee6ad73719562a028d806caf6c
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, with one prominent URL pointing to 'traffset.ru', suggesting a phishing or malware distribution campaign. The document body, though heavily obfuscated, appears to be a lure related to 'cognitive behavioral therapy worksheet', which is likely a pretext to drive traffic to the malicious URL.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://traffset.ru/strik?utm_term=abc+cognitive+behavioral+therapy+worksheet
    • https://cdn-cms.f-static.net/uploads/4410214/normal_5f9daf99bca51.pdf
    • https://cdn-cms.f-static.net/uploads/4367633/normal_5f98091dddc5b.pdf
    • https://cdn-cms.f-static.net/uploads/4365546/normal_5fa12325b613f.pdf
    • https://menuwenuxunok.weebly.com/uploads/1/3/4/6/134682317/zutad.pdf
    • https://cdn-cms.f-static.net/uploads/4368770/normal_5fab640f63285.pdf
    • https://cdn-cms.f-static.net/uploads/4393626/normal_5f8ffed98f23f.pdf
    • https://pozanabuloga.weebly.com/uploads/1/3/4/3/134366917/94efc.pdf
    • https://cdn-cms.f-static.net/uploads/4388432/normal_5f9ac0219a6b1.pdf
    • https://cdn-cms.f-static.net/uploads/4375357/normal_5f8bb7b3aff89.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/5cfab04d-3d13-4316-a2d3-83df1d1dfc9c/inner_child_worksheets_for_adults.pdf
    • https://uploads.strikinglycdn.com/files/de5b8bf1-d6f8-4067-b54c-bbe00a53cba2/buxopuje.pdf
    • https://uploads.strikinglycdn.com/files/72b57e29-35df-4aeb-9ba4-eff249d18667/12062999378.pdf
    • https://uploads.strikinglycdn.com/files/3b526041-17fc-40da-9e92-fa911ed63e8e/46512265688.pdf
    • https://uploads.strikinglycdn.com/files/cbd0ae88-b1cf-40a9-8983-0e924e90413f/64902438256.pdf
    • https://uploads.strikinglycdn.com/files/80b0b2d4-925f-4c60-b0b6-7fcd95b82beb/sanikolonusobun.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6c0.bin
9a419e7144d97097e8cf0c5b2da4ac71df96b4d10532ef97f6312817f4b974ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C0 5640 bytes
font_01_sfnt_off0000fa06.bin
01bc3b7f98d4b02ac07ac3415ff9091d668432b0f7b5d18cee1a45daa2c0f5ae
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA06 10768 bytes