Malicious PDF — malware analysis report

Static analysis result for SHA-256 1555bc8109a446d1…

MALICIOUS

PDF

80.8 KB Created: 2021-09-19 12:01:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4838dd5c48f83a943a4ce7132d771c9f SHA-1: 154b495aa953a7fb3169458f8db6275191bdedba SHA-256: 1555bc8109a446d1e51d1e9ba87aaf5701cde74266b0a84d2e1f92e8c7419aaf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution, aligning with the Spearphishing Attachment technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • 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://smidgel.ru/uplcv?utm_term=123movies+online+movies+finder
    • http://tce.vn/imagesflashupload/file/23493199484.pdf
    • http://zhodnoceni-penez.cz/is/images/FCKeditor/File/vufakuxulosomuzasexam.pdf
    • http://cuacuonanbinh.com/userfiles/file/bogeruribexevupemuj.pdf
    • https://computerzone.pk/file/gibiwatovibatev.pdf
    • http://xn--12cfu9bc1efac9a9azfdsb7b9d1f0j.net/ckfinder/userfiles/files/9749003651.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/161438c4dbeabd---lirilewudij.pdf
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/e1583ecaad28dcf8c6554c16b6aba3da/tisunenobixatukit.pdf
    • https://xn--90aweabvm.xn--p1ai/ckfinder/userfiles/files/46869943270.pdf
    • https://propiedades.net/ckfinder/userfiles/files/84099623007.pdf
    • https://nayyaralidada.net/alpha/ckfinder/userfiles/files/weguxobirufiba.pdf
    • http://s13cf5ef.alojamientovirtual.com/ropadefutbolbarata/userfiles/file/63398513860.pdf
    • http://studiopol.com/userfiles/files/xudavunagovu.pdf
    • https://tomorrowhubs.com/upload/users/files/59420118075.pdf
    • http://studiogaleazzo.eu/userfiles/files/41146532283.pdf
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/9eb3850538b0267c8ad0180ce21de3a3/35159624902.pdf
    • http://hueide.com/upload/files/viseduvamogejotozit.pdf
    • https://sportyou.fr/ckfinder/userfiles/files/20022513754.pdf
    • http://kimsanghun.com/upload/userfiles/file/202192848589609.pdf
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/ch7jqnf51jpn5kn8qbqraee627/suravelizegewivetoj.pdf
    • http://philipp-haberland.de/images/upload/file/topip.pdf
    • http://csptech.net/admin/userfiles/file/duguwez.pdf
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/haujhlglma7s70ps076gerqjlr/50728637740.pdf
    • http://restauraceeverest.cz/userfiles/file/bebigexoki.pdf
    • http://rayanchem.com/d/files/29480103720.pdf
    • https://fallsplat.se/bildbank/file/38327512120.pdf
    • http://mdsalon.ru/img/lib/file/17482397809.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d83c.bin
8cc1eabda95fc0a851be8c6dcbe275e9f5a132113758eb24642a56123db97155
pdf-font-stream PDF embedded font (sfnt) at offset 0xD83C 17824 bytes
font_01_sfnt_off00010556.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10556 16792 bytes
font_02_sfnt_off00011d6d.bin
2158b44d52eb4023a94fddddb9bd029e495abc53275869ad8ee67618645631f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6D 10568 bytes