Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0bcc51c65d86146…

MALICIOUS

PDF

70.7 KB Created: 2021-09-29 04:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7c56119da9641b138cdf97554170072a SHA-1: 30b63847a1e4b712fbb12cc1a20b08c6da7b45d8 SHA-256: a0bcc51c65d8614682936da0beae821f090bb64107367dc0d8a21ea129c51adc
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. The presence of multiple external URIs and link farm heuristics supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://chcial.ru/uplcv?utm_term=game+mmorpg+android+2021 PDF link annotation
    • http://trustycctv.com/ckfinder/userfiles/files/busesurerageriwosimu.pdfIn PDF document text
    • http://esebtekstil.com/resimler/files/vubibapejifereni.pdfIn PDF document text
    • http://xinchenfast.com/upload/file/kiguxosemena.pdfIn PDF document text
    • http://immobilieninvestors.net/userfiles/file/1772658493.pdfIn PDF document text
    • http://ttworld.hu/uploads/content_files/files/bufapofiwipeben.pdfIn PDF document text
    • http://jawarakreasi.com/file/11934565664.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/laxipojawuzet.pdfIn PDF document text
    • http://aodaibooking.com/FileData/ckfinder/files/20210909_74140DB81FA1F8BC.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613265ffc4021---nulaxevewipufekunalom.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614f196253829---budobikovugapa.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16136c0415f915---34272952554.pdfIn PDF document text
    • https://myvideoclasses.com/ci/userfiles/files/tigoguj.pdfIn PDF document text
    • http://perfekt-dom.pl/designhome/admin/userfiles/file/lipovitiximetumu.pdfIn PDF document text
    • http://rwdwebwebdesign.com/img-aim/files/xopedavozetoduz.pdfIn PDF document text
    • http://francescofesta.it/userfiles/files/4979591921.pdfIn PDF document text
    • https://dehaventransportation.com/home/de/public_html/ckfinder/userfiles/files/41269241950.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/paxonewaninavirirovipeli.pdfIn PDF document text
    • http://elfobchod.cz/foto/Image/file/rovomapategujidef.pdfIn PDF document text
    • https://oreopay57.com/ckfinder/userfiles/files/54827689477.pdfIn PDF document text
    • http://odontotecnicacoop.it/userfiles/file/kojuves.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/xisaboxonaz.pdfIn PDF document text
    • https://asken.as/bilder/file/nisazovuma.pdfIn PDF document text
    • http://giorgimpianti.com/userfiles/file/57620681546.pdfIn PDF document text
    • http://fusiongrup.ro/userfiles/file/lakirevewaxobifad.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/4abfa72e2d974727caa6849825cc7f87/97934564181.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_off0000b36f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB36F 16220 bytes
SHA-256: 4d83b2c2ac6419142ef6c111ade18c1ee4d8a3fc416c0477a0d659bdb790c93b
font_01_sfnt_off0000dc9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC9A 10756 bytes
SHA-256: ccae801b0839fe724bd81d7082f509b289de71c40c00840a9eedcc1b74839c43
font_02_sfnt_off0000f521.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF521 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1