Malicious PDF — malware analysis report

Static analysis result for SHA-256 db96237d4f5f9f1b…

MALICIOUS

PDF

72.8 KB Created: 2021-04-26 14:42:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: a958fb7e038ab13d764c3d579033a4c4 SHA-1: a97178de6e49a166ee9a4bcbf679046b239114c5 SHA-256: db96237d4f5f9f1b8bd2b6a2aaba02f7673cb659040de7688b2c394b162f4d59
186 Risk Score

Malware Insights

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

This PDF file contains numerous external links, many of which are hosted on disposable domains and utilize UTM parameters, indicating a link farm designed for phishing or malware distribution. The primary malicious URL identified is 'https://baarspo.ru/strik?utm_term=stochastic+calculus+for+finance+ii+pdf+download', which is likely used to serve a malicious payload. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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/strik?utm_term=stochastic+calculus+for+finance+ii+pdf+download PDF link annotation
    • https://cdn.sqhk.co/gorokipo/iiieChg/pubg_lite_pc_for_mac.pdfIn PDF document text
    • https://cdn.sqhk.co/borefigux/9ae0FCE/57332498072.pdfIn PDF document text
    • https://cdn.sqhk.co/vulovosovem/hcnERoK/ziwufasawopinefefujifamu.pdfIn PDF document text
    • https://dudefusuze.weebly.com/uploads/1/3/4/6/134628774/8188210.pdfIn PDF document text
    • https://xogexemufak.weebly.com/uploads/1/3/1/4/131437987/lejudatisovuxo-puxipotukom-dalekajirovomu-sodokitipire.pdfIn PDF document text
    • https://wawogikaso.weebly.com/uploads/1/3/4/7/134726687/tetovizapava_gabogexavenu_sakav.pdfIn PDF document text
    • https://kotezoxeruv.weebly.com/uploads/1/3/5/3/135345651/a51c08395.pdfIn PDF document text
    • https://cdn.sqhk.co/buvovemif/hgj8jeO/23311685369.pdfIn PDF document text
    • https://lasogevedona.weebly.com/uploads/1/3/1/3/131398076/8ab2e286b2ef9d3.pdfIn PDF document text
    • https://lonopenofof.weebly.com/uploads/1/3/4/8/134895818/mebozojutajek.pdfIn PDF document text
    • https://cdn.sqhk.co/gapalagabig/8gcha3R/7368885365.pdfIn PDF document text
    • https://cdn.sqhk.co/gixedomawa/9hh3pgc/65590458294.pdfIn PDF document text
    • https://zogoporev.weebly.com/uploads/1/3/1/3/131381602/zaxinabutiv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d6504552-49b0-4b7d-b1ff-94f9e1082b83.filesusr.com/ugd/1f0558_5f00b0af5f18417aa78a78934060c2fc.pdf?index=trueIn PDF document text
    • https://7f1888b6-cdab-4603-9914-1cf81a8b29aa.filesusr.com/ugd/6846fe_6b6968ffc29242b28d0343d860f2e714.pdf?index=trueIn PDF document text
    • https://8f1ef4f7-3f23-41ef-a3d6-4e5873a175a2.filesusr.com/ugd/d318ce_7b8030cec01a42c7a1055192d42bb647.pdf?index=trueIn PDF document text
    • https://1d942ef5-affb-47d8-8f99-70a3d187b733.filesusr.com/ugd/3283b0_da537c0a6dac4d49886de07d872c4f93.pdf?index=trueIn PDF document text
    • https://42e65457-ec34-4553-8979-78b6e302f774.filesusr.com/ugd/f1976d_c711587095c543c1b7ff22424ff1c478.pdf?index=trueIn PDF document text
    • https://56148a0a-83a3-4003-94ff-78d3044b7c00.filesusr.com/ugd/6f5f23_3d42a74c7f224d42afa6f3b233602539.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_off0000dc52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC52 5440 bytes
SHA-256: c74ce8486fb8022b35379a5c13467e8e4d6b58a4d8701d1155df27509acd84f1
font_01_sfnt_off0000eedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDD 11352 bytes
SHA-256: b6b6428a78683d3abcdd31ac9f95eb581a00ffb843db51b6bb804da97f0f1421