Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8a427bfdd2b604e…

MALICIOUS

PDF

90.4 KB Created: 2021-06-28 03:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8f8c45ba67fc3461bd7ad2e3343313df SHA-1: 3c46f3981bc8d0e021d464d40bfa3283d0766d9b SHA-256: a8a427bfdd2b604e650395d32b81c717bc17290c924016dc680d4ae266515668
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple compromised WordPress sites, likely to host malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, with the PDF being identified as a phishing trojan. The presence of numerous links on disposable hosting further supports a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0919727b8---kidasiza.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/kbmo9upummt7teae1avbjfptb5/riwovefajemazanuvokuwax.pdf
    • http://krevue.cz/UserFiles/File/gagixototodavezegifej.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/tlsbtnhirq921qbtttqei7f9sd/tofowopiteravojufuvoxo.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac8bed8f89c---5069180343.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609729b00309e---5474783857.pdf
    • http://huiking.cn/uploads/file/140957265557.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c701cf97c---28853048588.pdf
    • https://hrmconsulting.biz/upload/files/pajapudu.pdf
    • http://goraku-sangyo.com/userfiles/file/53975486497.pdf
    • http://sartor.ru/upload/files/tekeze.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160852d8d9775f---misowotemesifa.pdf
    • http://malagi.pl/user-files/fck/file/sefiwameledexaferukuzev.pdf
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/lkt53u85fj5tqt5q8ir03ofpc3/xabolurivitase.pdf
    • http://abacusnancy.com/userfiles/file/61618399640.pdf
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/5jvrti37vf3p2453ttjueqkdge/78506647264.pdf
    • http://handbook.hu/upload/page/file/dotilakinokedexunozowab.pdf
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a4bba03660a---20125558530.pdf
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/vlvqnk7059vto1rmovsv6amio7/batasifunofek.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b6860533dc9---tabezowewejozaven.pdf
    • http://curry-box-deluxe.de/userfiles/file/32910475039.pdf
    • http://maynenkhiinverter.com/media/ftp/file/xebexaxisiviximeve.pdf
    • https://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/64cd63412c315cbfbfb96a1983323795/rititabivigononalor.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/6b75185f92713d9b31702596c78c738d/sanomizonili.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba77a4cdabe---26023085414.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=i+need+rest
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bde8dde5ce---87796870249.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_off0001021d.bin
0cc68990c34048497b311dd3ef1f11a57fcbd6e28533f45c7d064718fd4185fc
pdf-font-stream PDF embedded font (sfnt) at offset 0x1021D 9772 bytes
font_01_sfnt_off00011796.bin
8c2e7d41645dbec414c16772e01052008f6a02399e0eda0c9a49d34181cc05c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x11796 17160 bytes
font_02_sfnt_off00014474.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14474 16792 bytes