Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4616fe284bf7cea…

MALICIOUS

PDF

106.9 KB Created: 2021-04-04 02:52:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 195d267b5df31face18de2fba23afed8 SHA-1: a3706582996078fb23ea14c4e37582fdbd660b19 SHA-256: a4616fe284bf7ceaf5bca778247e4772059bbbdef8d6d2edfb9f998f1c713554
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified by the PDF_SEO_LINK_FARM heuristic, suggesting it's part of a link farm operation. The ML classifier and ClamAV detection strongly indicate malicious intent, with ClamAV specifically flagging it as 'Pdf.Phishing.Trojan'. While no scripts were explicitly extracted, the nature of link farms often involves redirecting users to malicious sites or further payloads, aligning with phishing and trojan delivery tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://golowaki.ru/award?keyword=neoplasia+definition+pdf PDF link annotation
    • https://ritosameb.weebly.com/uploads/1/3/4/2/134266106/abaa0bceec6f1.pdfIn PDF document text
    • https://temabodanifow.weebly.com/uploads/1/3/1/4/131454916/ec8638a79b62.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477910/normal_6066ae8dc51a5.pdfIn PDF document text
    • https://buvejigu.weebly.com/uploads/1/3/4/3/134386374/4c65f057da305ad.pdfIn PDF document text
    • https://jivetigaforivuj.weebly.com/uploads/1/3/4/3/134350389/4f5888fa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477921/normal_603916f6e49f9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408002/normal_603b64fede47e.pdfIn PDF document text
    • https://penotogales.weebly.com/uploads/1/3/1/4/131438478/xuteke.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456119/normal_6056010199041.pdfIn PDF document text
    • https://liwevapazu.weebly.com/uploads/1/3/1/0/131071299/vexeliwojakum_sewadajenejejap_gefeboridikakab_pisuvivubupuram.pdfIn PDF document text
    • https://venunuwaxel.weebly.com/uploads/1/3/2/7/132740799/lixakeloxalovodumad.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/tojazudibumogab/the_bronze_horseman_book_free.pdfIn PDF document text
    • https://s3.amazonaws.com/dazutun/rimisawigikaropigosewe.pdfIn PDF document text
    • https://12f7643e-9106-4823-89c2-0bdaecd1bc22.filesusr.com/ugd/1f6d71_8faefae09a17429eaa7fc9585e32619d.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xalexojaxipud/que_es_aforismo_ejemplos.pdfIn PDF document text
    • https://ffcd7f67-9b43-45c2-8e44-b15cca9583b8.filesusr.com/ugd/48bf55_6ea22cdb22cf4d8bb31534baaa966f22.pdf?index=trueIn PDF document text
    • https://1ceef7f3-d523-4f80-a0a4-3aed54d3d17a.filesusr.com/ugd/48841a_15ef6519414240d79af6c88c02e1aa41.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015335.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15335 4696 bytes
SHA-256: 5980559cace138e7e91ce201036eda2e9e29bece14628253b4529c8cf12a8ceb
font_01_sfnt_off00016338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16338 13788 bytes
SHA-256: f63c7a4d413c77731436c461d5d3f906f5dad0011efc8284126231b5c12f0ffc
font_02_sfnt_off0001902e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1902E 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176