Malicious PDF — malware analysis report

Static analysis result for SHA-256 b840dd8b6922636a…

MALICIOUS

PDF

69.1 KB Created: 2021-03-31 21:52:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 237e55749f23cd1cf3ce631e8e901845 SHA-1: ec1020d19f17499d5e3d771538582b51f1925d85 SHA-256: b840dd8b6922636a9aabec7d69e0323ab9629abda77f5cb0e8a2b19c1a2f4449
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9992

Heuristics 6

  • 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 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://gimoguvi.ru/award?keyword=quimica+fisica+atkins+8+edicion+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4389568/normal_5fe1a545d065c.pdfIn PDF document text
    • https://zulufiki.weebly.com/uploads/1/3/4/6/134662959/tukewilijeden.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425772/normal_600c4bbfbb679.pdfIn PDF document text
    • https://lufisadoxusixa.weebly.com/uploads/1/3/4/5/134583632/1192081.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424364/normal_60225c7d87922.pdfIn PDF document text
    • https://govewusig.weebly.com/uploads/1/3/0/9/130969429/ditugudarunuju.pdfIn PDF document text
    • https://noduxexoretan.weebly.com/uploads/1/3/5/9/135993764/guvupokekalax.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489407/normal_605cf1f83a588.pdfIn PDF document text
    • https://lidafeli.weebly.com/uploads/1/3/4/6/134683499/701095.pdfIn PDF document text
    • https://cdn.sqhk.co/jemitaso/ggHghja/limbo_prime_price_2020.pdfIn PDF document text
    • https://gojajegu.weebly.com/uploads/1/3/6/0/136050346/kaxuma.pdfIn PDF document text
    • https://dametubidino.weebly.com/uploads/1/3/1/3/131383661/xesej.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380863/normal_60184c7720794.pdfIn PDF document text
    • https://ruvazokof.weebly.com/uploads/1/3/4/0/134040659/8851449.pdfIn PDF document text
    • https://cdn.sqhk.co/zaronafi/BCjbsbx/93332523025.pdfIn PDF document text
    • https://cdn.sqhk.co/pesuxitum/dhihfjf/file_manager_app_android_download.pdfIn PDF document text
    • https://cdn.sqhk.co/lawafopugu/iiaia0d/fufatizod.pdfIn PDF document text
    • https://cdn.sqhk.co/govuzupikiwe/W3ugWhd/cheats_for_gunblood.pdfIn PDF document text
    • https://sesubovokur.weebly.com/uploads/1/3/4/3/134311777/sawuzudovefip_kosab.pdfIn PDF document text
    • https://cdn.sqhk.co/ninoporaleva/ifPgdhh/joy_sunday_cross_stitch_reviews.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4cf6c2b4-cd84-4b73-83b1-bf7f441162b2.filesusr.com/ugd/e50c99_d5a9c234533c431ca7bcd71da57dba6a.pdf?index=trueIn PDF document text
    • https://952d9f4b-853a-4e85-af28-23c4d489d487.filesusr.com/ugd/8db125_40ad1764d7534c76bba65f7ec302153b.pdf?index=trueIn PDF document text
    • https://b3709dad-42f4-4621-9b7e-74d31ca978cd.filesusr.com/ugd/f91cf1_daff7bfb08ba4f5e80948fc653a61574.pdf?index=trueIn PDF document text
    • https://da9d63b4-fbfd-4f6f-88e7-06ac0d76355b.filesusr.com/ugd/ca300b_2852593b3efc4737903706e57a8cee13.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_off0000d011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD011 5492 bytes
SHA-256: 636030b9e651212fa7b37687ccda43658fa3d1961f241e4b88ad32122758a8be
font_01_sfnt_off0000e2b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B5 10596 bytes
SHA-256: 6815a678a53b26099a58d60c96bdc821a980a96a143b883b96e343ca99a05bbc