Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6158c5a98a0f253…

MALICIOUS

PDF

85.7 KB Created: 2021-03-29 00:21:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 0b7103deb653981007d71d6637272a7c SHA-1: 9bec5a7d27bf21161335e24c89f1d47e677a371e SHA-256: a6158c5a98a0f253bcf9299388c74905228610452c0c42f0666cf262d99ab95e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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 0.9998

Heuristics 5

  • 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 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://midufefew.ru/award?keyword=carcinoma+papilar+de+tiroides+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4481271/normal_6010962b8f068.pdfIn PDF document text
    • http://com-servers.online/budaxivowevegominomervv2la.pdfIn PDF document text
    • https://cdn.sqhk.co/kadeposamo/fP3uL3v/td_bank_auto_insurance_login.pdfIn PDF document text
    • http://itrom.fun/pagidonuraxaxatajukifelclxwd.pdfIn PDF document text
    • https://cdn.sqhk.co/fusunusol/ifbxUmj/block_breaker_3_gameloft_download.pdfIn PDF document text
    • http://mujoxoluvisukid.getenjoyment.net/sokelufe.pdfIn PDF document text
    • https://cdn.sqhk.co/wezupobuwab/geib2ha/skyview_lite_per_android.pdfIn PDF document text
    • http://meriline.store/bollywood_hd_movies_free_khatrimazamm495.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385859/normal_5fccc7abec1ad.pdfIn PDF document text
    • http://mebelintera.ru/5684002470075jkz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426812/normal_60328392d4c76.pdfIn PDF document text
    • http://itabody.space/sodeninerufanexakoto35pjx.pdfIn PDF document text
    • https://cdn.sqhk.co/vekuperik/gjgiKhK/lekivuruseviwijo.pdfIn PDF document text
    • https://cdn.sqhk.co/gufezima/gdhhjdY/management_skills_books.pdfIn PDF document text
    • https://cdn.sqhk.co/tubafejog/kFhbiaF/54184845269.pdfIn PDF document text
    • http://7lessons.fun/nitrogen_trichloride_polar_or_nonpolqlahc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426416/normal_6011053a4be82.pdfIn PDF document text
    • https://cdn.sqhk.co/woxiwokujuwe/gguowZ2/42685011831.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kulebosux.myartsonline.com/the_squat_challenge_gym_edition_free.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_off0000f75d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75D 5208 bytes
SHA-256: a449cf99a71646e172c00981c93145500505d8dbb36ded6fc92447b207fa8ff3
font_01_sfnt_off000108f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108F6 13312 bytes
SHA-256: 0cc5048b689263509a05fcdc4ad81b6bc2ddbc6025463f9ce32bd26c42c772b9
font_02_sfnt_off00013177.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13177 16304 bytes
SHA-256: 5ccf08c02617f6e393a73fced7b73c6365c68a663ae8ea59f1e4ce081e5fad7a