Malicious PDF — malware analysis report

Static analysis result for SHA-256 91135d77efbff61b…

MALICIOUS

PDF

76.6 KB Created: 2021-03-17 17:00:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2de58c8dc042b05314a756ca01b2d396 SHA-1: 68b3436cc46542733568e6d5c445372a033d74c2 SHA-256: 91135d77efbff61b894efbdd61a803de8980ff25d56a80355a6f4298bfff84b3
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a large number of external links, many pointing to disposable domains, suggesting a link farm or SEO spam operation designed to redirect users to potentially malicious content. While no scripts were explicitly extracted, the PDF structure and numerous external URIs indicate an attempt to lead users away from the document to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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
  • 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://bologen.ru/123?utm_term=google+sheets+freeze+row+mobile
    • http://vashastrahovka24.ru/faxibinegagezu4ftt.pdf
    • http://it50disconto.info/what_types_of_figurative_language_and_imagery_are_used_in_the_poem517px.pdf
    • https://busununivid.weebly.com/uploads/1/3/4/7/134774072/a9a16e63b9f4ac2.pdf
    • https://fanazogi.weebly.com/uploads/1/3/0/9/130969494/f22e09953.pdf
    • http://plusstore.pro/munemoxukebuhbx3x.pdf
    • https://cdn.sqhk.co/kotafuli/x2jljcv/ghost_cms_ios_app.pdf
    • https://daxexamuve.weebly.com/uploads/1/3/4/4/134446800/xovurolajelegap.pdf
    • https://cdn.sqhk.co/tireronerogo/wehjqot/99401610418.pdf
    • https://finedogu.weebly.com/uploads/1/3/4/7/134749629/tuwopifoka.pdf
    • https://gesurori.weebly.com/uploads/1/3/4/3/134353915/medanilo-vibozivuloxij-watisinelowukox-notomeb.pdf
    • https://mikedexe.weebly.com/uploads/1/3/1/4/131452733/junodexagam.pdf
    • http://afracheat1.xyz/canon_mg3520_driver_windows_xp8pt9d.pdf
    • https://zipuwuxa.weebly.com/uploads/1/3/4/3/134376087/a59c8e3c1652d2.pdf
    • http://urro-hu.com/wikukagaratojofagabemofursqt5.pdf
    • https://wozizagozesa.weebly.com/uploads/1/3/4/8/134848764/wowarefilujanug_nepuruw_pevan.pdf
    • https://norusukesalija.weebly.com/uploads/1/3/4/3/134356509/d097e.pdf
    • https://nakubinigana.weebly.com/uploads/1/3/1/3/131379761/renitiged-sewobamekibapo-dorasaniwugal.pdf
    • https://cdn.sqhk.co/sepokafaru/ichgl9s/ragaxuru.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/17a75f6b-15ac-46f7-a8f6-46294ea9755d/mother_night_kurt_vonnegut_movie.pdf
    • https://18e99e0c-7034-4a8c-9069-267580a295b8.filesusr.com/ugd/b337f5_aa888754b4d84ecebf065041173e7df4.pdf?index=true
    • https://uploads.strikinglycdn.com/files/ef60194e-f408-4a39-8db1-3d18058f946b/gibewufawobutuboze.pdf
    • https://uploads.strikinglycdn.com/files/962c3e34-8410-41da-9c8e-555425d278a9/dumanaloken.pdf
    • https://uploads.strikinglycdn.com/files/df92f398-4048-440d-a7fd-da4c3054171b/25886804044.pdf
    • https://e2604e0b-f95a-4acb-b53f-a7db3827b2a1.filesusr.com/ugd/225520_92587f3be36b46b5a7c8a6b872ff56b7.pdf?index=true
    • https://fea50346-ab34-4b67-843e-90a6383c4983.filesusr.com/ugd/bf678e_93d61042cc4a4727befd6f4a686ffcf8.pdf?index=true
    • https://3ae4d138-4ba3-4962-98fb-1b98b40a6a82.filesusr.com/ugd/38062a_66257058aecd4cdfae6ba7af25aa2724.pdf?index=true
    • https://8fc1c2d6-49ba-4d63-8b95-0327ef2b1627.filesusr.com/ugd/1849a1_98a924464ddd4f1eaae2ff997914df1f.pdf?index=true
    • 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_off0000ed50.bin
a9a97c5fa9241ee1a95d7029f124da8a9a45ef88f4740730f5ad2c66123c0939
pdf-font-stream PDF embedded font (sfnt) at offset 0xED50 5284 bytes
font_01_sfnt_off0000ff46.bin
44036ae9e6b09abfc40970220e027542c37484c46836e3fb91b8dd1b60ea7f40
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF46 10956 bytes