Malicious PDF — malware analysis report

Static analysis result for SHA-256 f2c5e424e18928c8…

MALICIOUS

PDF

91.0 KB Created: 2021-07-03 15:43:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: eb862460e308a8e7ef9192389cb41af1 SHA-1: ceffd6f92f66dfd5cf56f2290b54125c9f6268f0 SHA-256: f2c5e424e18928c8eea9646df689ee6dd360d9b7d9dd5aa75d65469ecc7bee7f
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a large number of embedded URLs, many pointing to compromised or disposable domains, suggesting a link farm or phishing lure. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://utuin.net/files/fckeditor/file/rekonidijibewiteto.pdf In PDF document text
    • https://schmitz.cz/res/file/18493172045.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/pidobuzitipoxikup.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/e9c7a7089b688358550751be3158cdc6/zadojawawixupi.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/467a4f36640da1bfe3c23b3223f1cb59/legasoj.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a46885868be---tulexosimupuri.pdfIn PDF document text
    • http://jnafarms.com/clients/864068/File/93437407442.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/16094cf7dea778---44655281897.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073af4a32e5f---vezad.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609f79882a218---38681793162.pdfIn PDF document text
    • http://rittenhousereunion.com/clients/a/ad/ad7d26974070b67854a29702aed78614/File/73960287733.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/fcmmi1vo7699qiec6ighve9idq/gelexudi.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/80d42e32965c36a682a9ffdd8cde6cf9/nukoteliwa.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/kixiligimigawuv.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/45349527229.pdfIn PDF document text
    • http://lso-msm.fr/userfiles/file/getavupiviridutosujisas.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/43505334537.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/h1mjr86sm3bd9o3jbbhek21pto/xopefufido.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/9283fc6397683e8aa7f3a9bc4852fedb/sojat.pdfIn PDF document text
    • https://area34.info/wp-content/plugins/super-forms/uploads/php/files/svr3k6ngs4sjs4o5crmp2nkg44/19770942137.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/9aba03b67e5bd52e25ea10c8e8c2a022/91912109227.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202105161457.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609466d40569f---25858977756.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3863de98db---55879295457.pdfIn PDF document text
    • http://billsky.ee/files/file/72856091251.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8450986d5---78173305491.pdfIn PDF document text
    • http://merrygoldholidays.com/ckfinder/userfiles/files/biziwuxikuxomadeg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=harvesting+methods+of+fruits+and+vegetablesPDF link annotation
    • 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_off00010212.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10212 16456 bytes
SHA-256: 46b72ae89ddab7887b4e2e6458ac4bfeef084fc85512d877be75c95b7470b28d
font_01_sfnt_off00012cb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000144cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144CB 11100 bytes
SHA-256: 04419fc24664018cf0df2054e92b0b5606b8cafab92bcf29d1803db1ea9dac10