Malicious PDF — malware analysis report

Static analysis result for SHA-256 f37cb3ae4ff8d938…

MALICIOUS

PDF

87.0 KB Created: 2021-04-03 15:22:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d89a17b8a7845a042b80027a62911f34 SHA-1: 44640fcfadd307336f55c9c7cc08350becdb30bd SHA-256: f37cb3ae4ff8d938617cffa47bb8c5592d901ae26018fed8ffb5d7e01a6e0ae7
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a large number of external links, suggesting a link farm or phishing attempt. The primary URL, 'https://zajinet.ru/aws?utm_term=how+to+repair+washing+machine+lid+switch+whirlpool', is presented in the context of a repair guide, a common lure for social engineering. No scripts were extracted, but the presence of numerous external links indicates a likely attempt to redirect users to malicious sites.

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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zajinet.ru/aws?utm_term=how+to+repair+washing+machine+lid+switch+whirlpool
    • https://cdn-cms.f-static.net/uploads/4454054/normal_605a7ab7cfa02.pdf
    • https://pivamaxisogen.weebly.com/uploads/1/3/4/4/134481881/7874190.pdf
    • https://static.s123-cdn-static.com/uploads/4393639/normal_5ff0c06a66a5b.pdf
    • https://cdn-cms.f-static.net/uploads/4402507/normal_6016a5ceab6a3.pdf
    • https://nitetawowi.weebly.com/uploads/1/3/5/3/135301411/9306678.pdf
    • https://cdn-cms.f-static.net/uploads/4365601/normal_6030d6061c7c9.pdf
    • https://static.s123-cdn-static.com/uploads/4409103/normal_5ff40d01b9c8d.pdf
    • https://pemopuxurumolu.weebly.com/uploads/1/3/2/6/132681293/5904380.pdf
    • https://cdn-cms.f-static.net/uploads/4368237/normal_604d2118ae848.pdf
    • https://cdn-cms.f-static.net/uploads/4470535/normal_601f9153c1088.pdf
    • https://sevimuxeso.weebly.com/uploads/1/3/0/7/130739978/353f3d.pdf
    • https://serofewaz.weebly.com/uploads/1/3/1/3/131379274/xubimune.pdf
    • https://cdn-cms.f-static.net/uploads/4366637/normal_5fda8ab3c6447.pdf
    • https://cdn-cms.f-static.net/uploads/4425759/normal_60168229c29a0.pdf
    • https://cdn-cms.f-static.net/uploads/4446283/normal_5fd79f2e86dec.pdf
    • https://static.s123-cdn-static.com/uploads/4393028/normal_5ff2642232d95.pdf
    • https://cdn-cms.f-static.net/uploads/4366959/normal_6017a82494602.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/33ee7971-eba3-4a37-9e54-8bd0dc6fea70/rasipobofolezuxusawuno.pdf
    • https://b5d51143-f34a-4a4f-9265-6917490cb775.filesusr.com/ugd/9f69bd_ff46cf0b28924501af46039645f0baec.pdf?index=true
    • https://fc060a1e-8c1d-4b7d-bafd-75f79d4c6355.filesusr.com/ugd/c0a468_59448cfcc7e0464a935ee97145b6c2e5.pdf?index=true
    • https://uploads.strikinglycdn.com/files/0d2dc604-4dff-4d02-8e78-6c9b24df12ee/mibaxurafixonave.pdf
    • https://uploads.strikinglycdn.com/files/152f4031-09fa-4e85-be9c-0b31e6de20a2/12241470186.pdf
    • 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_off000117e0.bin
cb29fe7e06a2672c08f5d0183e8ab12ef4cfa01adc53bf28cf82f58bbe3e4948
pdf-font-stream PDF embedded font (sfnt) at offset 0x117E0 5540 bytes
font_01_sfnt_off00012a99.bin
c63a373d03a197bae38b68f3971fd9864e37e39a4e6fcc9daed08832a3c27b2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A99 10420 bytes