Malicious PDF — malware analysis report

Static analysis result for SHA-256 f113520f920f27b2…

MALICIOUS

PDF

86.0 KB Created: 2021-04-03 10:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 5b245e8784ad9fa2de38d152fc3f27ba SHA-1: c05c5bf9ee1f04920259128fbdfafcb7f87bfa18 SHA-256: f113520f920f27b2694df53fb007ae35cb5e20054edc53774e19388d5b7f46b8
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the structure and numerous external URLs suggest it's designed to redirect users to potentially malicious content or further stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.
  • 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://ponafet.ru/award?keyword=tamil+nadu+railway+station+code+list+pdf+download PDF link annotation
    • https://kupelaranix.weebly.com/uploads/1/3/4/7/134729830/besaragilakil-dogaletegedasod-vovininap.pdfIn PDF document text
    • http://greatholl.com/distributed_systems_principles_and_paradigms-_tanenbaum_steenqoh7k.pdfIn PDF document text
    • http://clyb-wylcan3.space/xejumaloa8xls.pdfIn PDF document text
    • http://storeeu.info/paintshop_pro_x6xyb0b.pdfIn PDF document text
    • https://rotalexabif.weebly.com/uploads/1/3/1/3/131381819/basekovem-mekikeduli.pdfIn PDF document text
    • https://riwubabefos.weebly.com/uploads/1/3/4/5/134591520/3270229.pdfIn PDF document text
    • https://cdn.sqhk.co/panajevem/ogggegd/lightroom_editor_free.pdfIn PDF document text
    • http://sfhgfje5df.xyz/xafipubotalaxalvaao.pdfIn PDF document text
    • https://jefolujolu.weebly.com/uploads/1/3/6/0/136096950/bolomoj.pdfIn PDF document text
    • http://dezozuxuwok.iblogger.org/59764585897.pdfIn PDF document text
    • https://cdn.sqhk.co/bojexisebiwi/TJPumjh/tunelixabovorisenukebakez.pdfIn PDF document text
    • https://livesagu.weebly.com/uploads/1/3/1/4/131437401/189068.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://52cfbdcc-51c1-4e85-ba83-ad74149b4620.filesusr.com/ugd/93d431_226fa194f196400da6baa6a56bf8225e.pdf?index=trueIn PDF document text
    • http://pegivaruxonozef.rf.gd/bosejokelatebizerazu.pdfIn PDF document text
    • https://584abdf6-e408-48d3-a53c-4313a8f82471.filesusr.com/ugd/18ee90_d1fb5c7c9d5145998f86d754d94ced1b.pdf?index=trueIn PDF document text
    • http://zewesibapinite.epizy.com/95094431410.pdfIn PDF document text
    • https://4cd5a77a-be8d-44ba-8952-4177873115c4.filesusr.com/ugd/930050_123a7d164c494953b5298d452a8999f2.pdf?index=trueIn PDF document text
    • https://aece7fbc-7072-4055-9cfa-29e0da41b620.filesusr.com/ugd/e878fd_c542f441e6ff41acb2398993ec626537.pdf?index=trueIn PDF document text
    • https://71347f20-8353-4153-bebc-dd2a28b3a5cf.filesusr.com/ugd/a382ee_15833db3e5b044e0a7a499e94b90f226.pdf?index=trueIn PDF document text
    • https://aa700e4b-9450-4a85-8b7e-8c92ffe47626.filesusr.com/ugd/de972d_2dcdf82f132c401bb294f77403240548.pdf?index=trueIn PDF document text
    • https://72cdfa97-b5fe-44cc-9aa9-3142b5aa642a.filesusr.com/ugd/ee32c9_333d902376e948529ad89ddf1841fafb.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000111a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111A8 5444 bytes
SHA-256: cb630ae40df84f0a87c310dfca84283a22362482045c50a5f6ae357c7f483762
font_01_sfnt_off00012431.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12431 10524 bytes
SHA-256: e7a1002166d2eaa79a2ded33d738a09cb8e5c1b1ce96acbe8e83f29185acd591