Malicious PDF — malware analysis report

Static analysis result for SHA-256 657f256f12966eec…

MALICIOUS

PDF

75.8 KB Created: 2021-09-22 23:04:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b61483c4ea1af75097d5f91f79bcd4ce SHA-1: 361b37c5065c1736900e56fd086746a036b712d9 SHA-256: 657f256f12966eec2e35a7cb64b08fc04db50024262a6a2f0690afb96a95f3ab
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is often used to redirect users to malicious sites or download further payloads. The PDF also contains numerous external URIs, many pointing to disposable domains, and is flagged as a link farm. ClamAV detection and ML classification strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://krisoc.ru/uplcv?utm_term=email+intent+android+kotlin PDF link annotation
    • http://laserinnsbruck.com/static/vadovapogupowebivag.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/92332059265.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/jepivilukapavixezawajumax.pdfIn PDF document text
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/69638737477.pdfIn PDF document text
    • http://nagakuratrading.com/js/upload/files/rupidaxowen.pdfIn PDF document text
    • http://branonperformance.com/ckfinder/userfiles/files/venekejufirubudojoj.pdfIn PDF document text
    • http://badgerhillfarm.uk/19961888868.pdfIn PDF document text
    • http://rentbucharest.net/images/userfiles/57145160159.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/furilabovijaviremelagi.pdfIn PDF document text
    • https://inprovit.com/ckfinder/userfiles/files/21468956848.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/vusozexijarojapirigas.pdfIn PDF document text
    • http://auroraenergyproject.it/userfiles/files/dikuvavewinijoj.pdfIn PDF document text
    • http://euskararenginkana.eus/files/galeria/files/nukaroganetir.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/9baabec6410873f037bbfb3bb444ffa8/zesopiwomubu.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210914_46A082E6A8DF9B8E.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/zazibefijuxowilazuku.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/vugomovovoxozapovojoni.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/753868c9f8fcca363e7752871f8c17cb/73722772415.pdfIn PDF document text
    • http://crmloccitanecr.com/campannas/file/74213222499.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/46534993539.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/17374266519.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/togisoz.pdfIn PDF document text
    • http://exmar.it/foto_fck/file/zuritumisa.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/96416637929.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://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_off0000c384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC384 18108 bytes
SHA-256: b9c7f38df7dbbd72a96ab1fabbdfc130673425f15b2dba4d952ac32dc0cc0f31
font_01_sfnt_off0000f226.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF226 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3D 10316 bytes
SHA-256: 529744bfb9f9b199e05d5d133cb07af1807f8309223b57958e31d5ee80797156