Malicious PDF — malware analysis report

Static analysis result for SHA-256 40ab1953078d6169…

MALICIOUS

PDF

90.0 KB Created: 2021-03-06 14:35:02 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 185c706f9e91ca4577a337f395a632e6 SHA-1: 8efcab3d617e3f3fdbcb5d9f92b22b01f0c2cc8a SHA-256: 40ab1953078d6169cf4a429d1cc70a8c2166439fd80cfc90db0aad76ce047759
246 Risk Score

Malware Insights

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

This PDF file is identified as malicious by multiple heuristics and a machine learning classifier. It contains a link farm with numerous external links, many pointing to disposable hosting, and specifically includes a credential phishing lure impersonating Microsoft. The document body, though heavily obfuscated, contains text related to job searches, likely a pretext for the phishing links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://liberiloro.weebly.com/uploads/1/3/4/5/134589576/616a8647a.pdf.
  • 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://resalured.ru/award?keyword=assistant+educational+psychologist+jobs+london PDF link annotation
    • https://cdn.sqhk.co/zegegajugot/4XiblZS/hearthstone_meta_report_august_2019.pdfIn PDF document text
    • https://cdn.sqhk.co/texojijoraso/1E58tiG/follower_count_twitch_streamlabs.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368736/normal_6005ae6cc1f38.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495387/normal_60032d68b247a.pdfIn PDF document text
    • https://cdn.sqhk.co/mekaxosur/ijjaig9/male_wolf_reader_x_rwby_wattpad.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477629/normal_5fe4f1857dd46.pdfIn PDF document text
    • https://liberiloro.weebly.com/uploads/1/3/4/5/134589576/616a8647a.pdfIn PDF document text
    • https://cdn.sqhk.co/vupapevixu/cij2hbU/tumonifibutisiw.pdfIn PDF document text
    • https://vemosigexirapi.weebly.com/uploads/1/3/4/3/134387812/8448162.pdfIn PDF document text
    • https://cdn.sqhk.co/noperizapewo/jCqLMgi/81805042752.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381340/normal_602cdfa186b74.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483097/normal_60232d3ba8ac0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nugafafekovad.epizy.com/90682642726.pdfIn PDF document text
    • http://wegupowir.rf.gd/303_tricky_chess_tactics_free.pdfIn PDF document text
    • https://5c817321-7c0c-448b-959d-deb1da9fd788.filesusr.com/ugd/19103d_7df76ba1cd304b82b8516b8c7da353cb.pdf?index=trueIn PDF document text
    • https://d86ad34a-7df2-4f47-937b-a12ab5abc0fa.filesusr.com/ugd/8cbfce_6ad119402ba64991a4fcf0aa41a3b39d.pdf?index=trueIn PDF document text
    • https://917ed8d3-8a9f-4c5c-a3ad-554e533308ad.filesusr.com/ugd/a4e402_7760fcbeadd342069d82695c4bd834f3.pdf?index=trueIn PDF document text
    • https://cee4a208-09ac-40e0-983f-4c2cc776acbe.filesusr.com/ugd/5ed537_abb4cd91ddb84bc8a3135931314a0f06.pdf?index=trueIn PDF document text
    • http://xegunapajom.epizy.com/35595400225.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_off000123eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123EB 5544 bytes
SHA-256: 865f0282c0ea681bc6b0b0ffec5de90135fd046dee066eb6496d7c2ec02f0242
font_01_sfnt_off000136cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136CF 10476 bytes
SHA-256: 569307a676f6aca4b47801abe24c7cc87e171556743cff3671ff88094ee2e100