Malicious PDF — malware analysis report

Static analysis result for SHA-256 88a613fbc69d04e1…

MALICIOUS

PDF

96.4 KB Created: 2021-09-18 03:13:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fd88ef061af2b6fd36f0d62db61a8f1a SHA-1: 6f3cb4787dd5f7e4bd4b65e1e9a92031e14127cf SHA-256: 88a613fbc69d04e1b19c6e53fc0d811b6e92341dd9415dea635dd805b54ac514
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document contains numerous links to disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were extracted, the embedded URLs and link farm nature point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 http://platypusspot.org/uploads/ckfinder/userfiles/files/dosafezeripe.pdf In PDF document text
    • http://kokocurry.gm/userfiles/file/50201538215.pdfIn PDF document text
    • https://fuze-pay.com/ckfinder/userfiles/files/kitoxe.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/xazoxibufesoguvalazegesu.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021091306241063.pdfIn PDF document text
    • http://dispensapertutti.com/userfiles/files/berurirudewi.pdfIn PDF document text
    • https://parfumzone.ro/files/file/99413702992.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/67805139120.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/kojupemi.pdfIn PDF document text
    • http://cisseo.net/userfiles/files/47819623662.pdfIn PDF document text
    • http://sinners-party.de/media/file/44357760021.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/fonafo.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/29281903251.pdfIn PDF document text
    • http://velkoobchod-man.eu/ckfinder/userfiles/files/girazafanifaludadobipe.pdfIn PDF document text
    • http://www.leposeur.fr/site/upload/ckfinder/files/xulix.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/bomezulomonepobebavujito.pdfIn PDF document text
    • http://doradcyprawni.com/images/pliki/192530173.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/9l8o1lub0t3i9v1k5ibetulbi3/dukepupotevupag.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/gemodanowobosasi.pdfIn PDF document text
    • https://sapporomn.com/userfiles/files/96516111477.pdfIn PDF document text
    • https://langumeistras.lt/i/File/jefiwu.pdfIn PDF document text
    • http://vsrru.ru/userfiles/file/wuxixinenalekojatunuru.pdfIn PDF document text
    • https://am-system.eu/ckfinder/userfiles/files/bavolijerirageteborajugag.pdfIn PDF document text
    • https://www.ewdel.cz/ckfinder/userfiles/files/rijuje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=ram+full+moviePDF 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_off000117d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D1 17484 bytes
SHA-256: 183f5c3aeca95c3ddf28db7805d232ffc7637bfea5e430de5d595c8ad12e9619
font_01_sfnt_off0001450d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1450D 10116 bytes
SHA-256: 0eb8d7912e2d78b4adbca2246944cfda231ba35769fa58b7c1f8bd52bf7d706a
font_02_sfnt_off00015bac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15BAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1