Malicious PDF — malware analysis report

Static analysis result for SHA-256 35fba2a2135b840c…

MALICIOUS

PDF

84.8 KB Created: 2021-07-19 05:21:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 01d9b1025a59f83fca16fa97c24e4e21 SHA-1: 7f21f0d0f246ece9addab47b1ea645195d9b2cab SHA-256: 35fba2a2135b840cfbed7318325c955d90561566b67cd62c7f67294693196920
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://hitecds.com/userfiles/file/titenufirazudasuviv.pdf
    • http://aarogyamedico.com/userfiles/file/54479423153.pdf
    • http://comp-art.ru/userfiles/file/zujin.pdf
    • https://shen-su.eu/gfx/userfiles/files/rozekoxo.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160f4bc7fd8777---molijareniziwuzinaz.pdf
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f898b67821---81813034613.pdf
    • http://saintthomasmonrovia.org/clients/a/a7/a774d5b45fc75aba9c6fcf07501e1e58/File/pexuxalosebirotazaxegifa.pdf
    • https://bruceleevideos.org/images/file/mewab.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ddf8f6baa8---52373968474.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5cc9d5488---66403050815.pdf
    • http://stin-verdon.fr/assets/Image//files/1232573723.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4369b7114---kavidusare.pdf
    • http://rdmsrl.it/userfiles/files/vamat.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607570d49e488---86643683115.pdf
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/812684cd3f1cf1c0594810c9e7517830/49067140781.pdf
    • http://adance0112.com/upfile/editor/file/53127085051.pdf
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/9842gvn44ac2pr6gq2jcm205v6/69120865291.pdf
    • http://urgentcarepb.net/userfiles/file/12650306825.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/i16oa191elqjmfar62583hjad3/bolobolorolakegem.pdf
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16083b4863b5f8---pavunixexinokijume.pdf
    • http://toyteepee.com/uploadfiles/file/210517195342772754x2wwk7.pdf
    • https://torbay.ru/images/uploads/file/18665480638.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=first+branchial+cleft+fistula
    • 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_off0000ea67.bin
7c54a49c889761f1a62141be4de5f473505b40053cb88f5c43f76a537796cc24
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA67 10532 bytes
font_01_sfnt_off0001024b.bin
68c81a7984909ce20ae0099a64cf6d2cc365d657205bac42a46f014141f3106a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1024B 16256 bytes
font_02_sfnt_off00012c8e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C8E 16792 bytes