Malicious PDF — malware analysis report

Static analysis result for SHA-256 522056792b9f68f6…

MALICIOUS

PDF

95.3 KB Created: 2021-06-13 23:57:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 44bfdfc8443e7b45cc3aee6d67480988 SHA-1: caeafa6d1fb0214e72b320cf9b3d0aefcacb5ada SHA-256: 522056792b9f68f660a49c14531220ae4080c7f18b3b9c2984973de522e01200
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. One of the primary links, 'https://baarspo.ru/123?utm_term=arithmetic+and+reasoning+books+in+telugu+pdf', is likely part of this malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://baarspo.ru/123?utm_term=arithmetic+and+reasoning+books+in+telugu+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4443326/normal_602a4929c07a5.pdfIn PDF document text
    • https://tisuzibe.weebly.com/uploads/1/3/1/3/131379312/girug.pdfIn PDF document text
    • https://wadezirukabag.weebly.com/uploads/1/3/4/6/134668274/1654319.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477886/normal_5fc9ec26677fc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375907/normal_60510154ed40d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494451/normal_60469cc89df0b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461766/normal_604ef72e690f0.pdfIn PDF document text
    • https://zukedobawalot.weebly.com/uploads/1/3/4/5/134526307/fagababisabo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447626/normal_6027198b7ecd6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368751/normal_5ff3844cb0f7f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418991/normal_5ff29796809e6.pdfIn PDF document text
    • https://rolosakuzorega.weebly.com/uploads/1/3/1/3/131379035/jomiruse.pdfIn PDF document text
    • https://gixipimeno.weebly.com/uploads/1/3/4/3/134310045/kerosogekowivex_potesew_rediwerobexise.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414682/normal_6049c7c4ae510.pdfIn PDF document text
    • https://roresino.weebly.com/uploads/1/3/4/3/134364893/mabuwunapofofiga.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366397/normal_6027da5b113be.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://nilidix.pbworks.com/f/nds_emulator_for_chromebook.pdfIn PDF document text
    • http://febamizilaw.pbworks.com/w/file/fetch/144893298/luviwuxokiromadapevafelug.pdfIn PDF document text
    • http://bezagodo.pbworks.com/w/file/fetch/144600522/wazex.pdfIn PDF document text
    • http://pesivop.pbworks.com/f/mizufojetunenerovolerid.pdfIn PDF document text
    • http://tewabavuxate.pbworks.com/w/file/fetch/144780564/the_encyclopedia_of_crystals.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_off0000ffdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFDF 5760 bytes
SHA-256: 5be4692d562d7506eac1d0e8abfc532fea2efbdfc81425981ab60553c3a956d0
font_01_sfnt_off00011348.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11348 26120 bytes
SHA-256: 363d8483bcbfd4982f39f74f1724237387d5e44eaa602f600d510a90f40ba321
font_02_sfnt_off00014c98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C98 10112 bytes
SHA-256: d04b5a2231988e066d37a3608d53f4fcd4334e79754c164707f5e3703f6d3763