Malicious PDF — malware analysis report

Static analysis result for SHA-256 5885520244145d29…

MALICIOUS

PDF

77.2 KB Created: 2021-04-03 19:07:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 8ce9684195e6062b79277d5c341ff58b SHA-1: b8e740bed430337216b6c18db4e23572bd6bc768 SHA-256: 5885520244145d2944a4644797211b9e441e68b007633115055057671d2174f1
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm designed to attract traffic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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 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://nipisod.ru/award?keyword=algebra+1+formulas+sheet+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4463794/normal_60488c11bc46f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4504922/normal_5fd636ea66deb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406169/normal_60641535568b9.pdfIn PDF document text
    • http://suboxobuwofum.iblogger.org/fotuwujabi.pdfIn PDF document text
    • https://cdn.sqhk.co/gibuburi/Nz1wTgj/zirojodawemasat.pdfIn PDF document text
    • https://cdn.sqhk.co/girewobo/ejhjcig/halloween_2020_movie_releases.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368777/normal_603d4c292e950.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386354/normal_605a2efe04488.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411682/normal_6002f15a1113a.pdfIn PDF document text
    • https://cdn.sqhk.co/mikedeto/rZhciig/is_smart_balance_oil_blend_gluten_free.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412774/normal_602a02751bb48.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://aa514bbb-a96e-4bc9-8ff3-0ca2edd1104f.filesusr.com/ugd/3fc21f_9853c8c0e5c848f1ad6745b60316d118.pdf?index=trueIn PDF document text
    • https://493f174a-a540-412c-bacb-e5b7b26cbfcf.filesusr.com/ugd/95bb70_c360825c15b74571a0df5cd9818c2169.pdf?index=trueIn PDF document text
    • https://6bb2b61b-82bf-473b-8365-63ddb02ddbdd.filesusr.com/ugd/d55797_568bc9cdc4af444190cf3ed7ba769774.pdf?index=trueIn PDF document text
    • http://paxokebarunune.rf.gd/22121287830.pdfIn PDF document text
    • https://s3.amazonaws.com/pugomonapoxuxe/backup_android_game_data_to_pc.pdfIn PDF document text
    • https://4adff18d-dc39-4349-be2c-eeb12737f1cb.filesusr.com/ugd/9117e0_92ac909351dd4499a0aa536abc2252dd.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dukexajuj/rezabimadujozefav.pdfIn PDF document text
    • https://d7301f0f-9730-4f6e-9d95-601e203cb770.filesusr.com/ugd/253413_7a616e7fcd25498395319219b845c5b5.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/loxopudizus/all_over_print_t_shirt_template.pdfIn 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_off0000dfe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE5 5364 bytes
SHA-256: c2c9db806bb43e7e77117d43ac770305d3ca579430932dce521d137b2dfcefab
font_01_sfnt_off0000f228.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF228 11496 bytes
SHA-256: b5406c4d207c77a1915de32628a0c4940af551b65ff28243f8379407ea441e9d
font_02_sfnt_off00011971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11971 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71