Malicious PDF — malware analysis report

Static analysis result for SHA-256 19b4f6857e5dedc8…

MALICIOUS

PDF

77.4 KB Created: 2021-06-11 10:10:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: a9b8ca44c9a8089956eac9f101fa6d87 SHA-1: 1ccaae3f9d4f27b4787c6b164e3a2008f14d65b1 SHA-256: 19b4f6857e5dedc8d5525c401ca35975b16bf85470d802c49446b199ceeafdc3
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an MFA/2FA-themed lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • 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.
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://oniceh.ru/pbw?utm_term=how+to+transfer+money+from+cash+app+to+my+debit+card PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4390663/normal_6011f20634f3a.pdfIn PDF document text
    • https://kesegupopu.weebly.com/uploads/1/3/4/1/134131766/4015b6.pdfIn PDF document text
    • https://dudegakabiwuzab.weebly.com/uploads/1/3/1/4/131406663/vepefovi-rerugorixoxemu-gokagi-sunexurubotiv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409257/normal_6035117951051.pdfIn PDF document text
    • https://xediziku.weebly.com/uploads/1/3/1/3/131384396/linukoziselowi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366312/normal_604205455e11c.pdfIn PDF document text
    • https://renupipa.weebly.com/uploads/1/3/4/3/134383378/fokeguxadeka_pefazuxuse_goborizalibit.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388169/normal_6051e03d230b8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500889/normal_6063cfd7542fe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383449/normal_5feaff163ca16.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474989/normal_606a8d54637d7.pdfIn PDF document text
    • https://vobokalonumenu.weebly.com/uploads/1/3/4/6/134656332/2453680.pdfIn PDF document text
    • https://xofanasafavusov.weebly.com/uploads/1/3/4/3/134399160/5790197.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481154/normal_6012811a2c84f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367650/normal_5ff448135d4e6.pdfIn PDF document text
    • https://luvalebasewe.weebly.com/uploads/1/3/5/3/135326782/juwisopiga_javulojapuzomu_xumadadodi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zuvuzut.pbworks.com/f/krte_ilahi_mevlid_mp3_indir.pdfIn PDF document text
    • http://gulisapil.pbworks.com/f/98738662490.pdfIn PDF document text
    • http://nusuwoxub.pbworks.com/w/file/fetch/144812505/how_to_use_self_inflating_camping_mat.pdfIn PDF document text
    • http://risuxujuvu.pbworks.com/w/file/fetch/144520587/sram_guide_r_brake_problems.pdfIn PDF document text
    • http://suxaraxep.pbworks.com/w/file/fetch/145074498/2133379812.pdfIn PDF document text
    • http://feteselulo.pbworks.com/f/fox_8_news_caster_dies.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0C 5660 bytes
SHA-256: 87c3e3a3f6a0376140e1414d4493ef187b302353e7b070dfe57090616ec493cc
font_01_sfnt_off0001022f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022F 11156 bytes
SHA-256: ce8f38ee9c47f6477336c5827014cee662e28aabca959ba37d645300fe30d2de