Malicious PDF — malware analysis report

Static analysis result for SHA-256 227cb9c91b31049a…

MALICIOUS

PDF

103.3 KB Created: 2021-06-27 12:29:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 782304c6ef073615bb56062a49514530 SHA-1: fa242294b4903367416bbc1efabca0d7fc9d59bc SHA-256: 227cb9c91b31049ad902d1875714d8dcbb9a6e234a2060ceba0f6e6b62646df1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised WordPress upload directories, forming a link farm. These links likely serve as redirects to malicious sites, as indicated by the ML classifier and ClamAV detection. The primary purpose appears to be directing users to phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9767

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://pistant.ru/uplcv?utm_term=the+meaning+of+naphtali
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf945ebd46---javikinofedunesitupukuz.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/8cocvn89n9cbb1f2vogitgur70/kesel.pdf
    • https://alutat.com/data/file/43332701823.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160bf8918e8c98---87541092141.pdf
    • http://praxis-greve-polley.de/web/editor/files/femuzipe.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/2bf4d4a4ae713b5a59a2d9cdf79edfd9/82229451318.pdf
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607434ce01601---15225291745.pdf
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/70ade546ce8873fc3b61a5214b04979a/29127945755.pdf
    • http://playfromhome.org/clients/4/49/49939bf6a151252ba1adfe53d1befa29/File/temezamosakefupuzusezixid.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607609abf1106---25912871068.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/2ef36cb4dde0ee5b1ae77ca08013b23d/xafesij.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/444d891ad5382707bfa88c067e1acd83/65359880838.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/83c895f3495baf51de0551aaa43e4a45/93410271941.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/c274ab242d5ca9a18fbb94c057ffa800/xawekezex.pdf
    • https://pointswestliving.com/ckfinder/userfiles/files/54091144194.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c470cb33ade---50144342829.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160713bdb57668---43681689446.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2de49e70c1---renimorotafex.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/917u1h5gbl01pubmj0bkls1bp2/kafekomepabefafasosuvogif.pdf
    • http://dreiseengrundschule.de/files/52257875554.pdf
    • http://sungsam.net/userData/board/file/67155093610.pdf
    • http://ahkjt.com/upfile/file/50774130778.pdf
    • http://yasaitogo.com/uploads/files/puzosazokaz.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/823cf36933807b5be06064e48952c77e/dunobetagilalejaw.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/917a821491ba4ab97d55f69d42a6561a/6063851585.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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off0000fb24.bin
121c8586814db26aef4528d6dd2b9ce3b25ba46d3a2379db5d0300b7f3bd8257
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xFB24 18008 bytes
font_01_sfnt_off000117c2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x117C2 16792 bytes
font_02_sfnt_off00012fd9.bin
93778d9baae3c920413d461beedf70bb9ef6c174cffcfe23cda68a612681ecc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12FD9 10500 bytes
font_03_sfnt_off00014778.bin
371d9c4c1ce7beb006e5c85122136950e3392b98075900b1859531656d3e2b53
pdf-font-stream PDF embedded font (sfnt) at offset 0x14778 3300 bytes
font_04_sfnt_off000154cd.bin
d90c26226cdd9fccf2d615a04283be2a1f8cc17445949a5ae7c1e1da2eb9bbd7
pdf-font-stream PDF embedded font (sfnt) at offset 0x154CD 22488 bytes