Malicious PDF — malware analysis report

Static analysis result for SHA-256 e91fa9fbc1e9b7d4…

MALICIOUS

PDF

88.4 KB Created: 2021-04-02 09:30:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: f43faa13c7da05774e9e534e6605cfdb SHA-1: a0f88ef5f97f9d5a07cc6608ed94df59a5189d18 SHA-256: e91fa9fbc1e9b7d472abcab16a54dd36f5f4620adfc28d051c4a7f27bbec7d87
126 Risk Score

Malware Insights

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

The PDF contains numerous external URIs, many pointing to disposable hosting, and is flagged by ML classifiers and ClamAV as malicious. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. The presence of embedded URLs further supports the attack pattern of luring users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://jacksth.ru/strik?utm_term=the+barbell+prescription+free+pdf PDF link annotation
    • http://frasqen.online/kufawifilumifikugettvl08.pdfIn PDF document text
    • https://cdn.sqhk.co/worijekegir/efijbV0/citadel_forged_with_fire_xbox_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/rixutixim/ZwidbnS/ghost_hunters_hulu.pdfIn PDF document text
    • http://thrivewebs.com/tibofngpw8.pdfIn PDF document text
    • https://cdn.sqhk.co/tazifawixax/ihgd3BQ/ganipularunofo.pdfIn PDF document text
    • https://cdn.sqhk.co/vekotevudoze/bUaigdl/throne_chairs_for_rent_in_memphis_tn.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453914/normal_60571a0b7fdeb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369520/normal_60663a26757d0.pdfIn PDF document text
    • https://dilemawusufugo.weebly.com/uploads/1/3/0/8/130874642/vuvidow.pdfIn PDF document text
    • http://moshon.space/final_space_hentaiqi9zl.pdfIn PDF document text
    • https://losaburi.weebly.com/uploads/1/3/5/3/135322327/dekuralawixabe-barizefamewusaw-zikuv-bejekagej.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475577/normal_60639dc9eae81.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405437/normal_60009402dd7a9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426409/normal_5fdbbc6461993.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gavojomizam.epizy.com/36394707937.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c68d111c-ce38-4370-a36f-4f0aed42cc47/vaxekatitimomexusadej.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6cbff8a1-9c3a-4ad4-aedb-d51a950b4685/siwetugarukapewoxa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6cb50bc3-bf85-42db-9f70-c7af6d0eaf47/which_love_language_are_you_test.pdfIn PDF document text
    • http://roxubimolileko.epizy.com/contest_winner_release_form_template.pdfIn PDF document text
    • http://fapadetesiwix.rf.gd/vilesijazatalaminepopemi.pdfIn PDF document text
    • http://josetevuj.epizy.com/marine_corps_boot_camp_training.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b31481e-78c8-41c2-877f-035e88c67422/54586568380.pdfIn PDF document text
    • http://jenofabejuvokag.epizy.com/hindustan_unilever_annual_report_2015-_16.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000106d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D0 5332 bytes
SHA-256: ac9585d687b4714870b3ace2588ee03bc79b2d9c13b1009ca5d2cbd91a23eee4
font_01_sfnt_off000118dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118DC 9008 bytes
SHA-256: 37ad692d0b1c70e48df69f7eba2f591136dd02cf80c4f79fa6f313b1a144dbee
font_02_sfnt_off00012b03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B03 11824 bytes
SHA-256: 1ea10091e0064059081cde5756170124ead9229fb30e0cb5942440de0ffe550b