Malicious PDF — malware analysis report

Static analysis result for SHA-256 e274ea82100b395b…

MALICIOUS

PDF

84.6 KB Created: 2021-09-22 14:27:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2fae815f6a47c2221c2d687356dc6586 SHA-1: 2cb724a9005a95f77af2484e138c579e77d0dcb4 SHA-256: e274ea82100b395b34a600ea25ae6f7189f5767ddf769ca621753b174a052251
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous links to disposable domains, suggesting an attempt to direct users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://5ky13lu3-1251.com/contents/files/28315662582.pdf In PDF document text
    • https://ksuskalology.com/images/file/mivaviturive.pdfIn PDF document text
    • http://kingkady.cn/uploadfile/files/sesutelotisaxovibugifed.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/gatuteguto.pdfIn PDF document text
    • http://motivationandmomentum.net/ci/userfiles/files/40584465831.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/29275679415.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/bugeliti.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16146a036e5124---43042780721.pdfIn PDF document text
    • https://tasivn.com/upload/ck/files/68264406685.pdfIn PDF document text
    • http://www.serge-valentin.net/ckfinder/userfiles/files/xukigidutopajavulafapa.pdfIn PDF document text
    • http://directopinion.biz/uploads/FCK_files/file/15735591788.pdfIn PDF document text
    • http://starinviter.com/ckimagefiles/66186353096.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/58795472162.pdfIn PDF document text
    • http://atletika-pardubice.cz/files/file/riretevotor.pdfIn PDF document text
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/gavinavinonajulewu.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/subeveten.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-20/20210920102655347219.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/dumonum.pdfIn PDF document text
    • https://drivetripper.com/userfiles2020/files/gobafaguruxajifukotevu.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/sofalawupakuzedepogi.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/4276339234.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/rulobaludux.pdfIn PDF document text
    • https://togelunited4d.com/contents/files/22311657775.pdfIn PDF document text
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/36795811585.pdfIn PDF document text
    • http://kalkulacka-hypo.cz/userfiles/files/wunovezejuwutuzumujaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=sell+your+haunted+house+ep+7+eng+subPDF link annotation
    • 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://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_off0000e386.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE386 18032 bytes
SHA-256: 4c96fee938e47448075cf248144f27ea4215ecd6264cddb06d844b27ecdb078d
font_01_sfnt_off000112ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112AB 11056 bytes
SHA-256: dca854c4f1e2de7bf72e00e35805926f58e8080027b91330a38e9566169690c4
font_02_sfnt_off00012c0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1