Malicious PDF — malware analysis report

Static analysis result for SHA-256 b641f2cb006fdf59…

MALICIOUS

PDF

97.2 KB Created: 2021-07-16 14:08:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1e518c1267b5a85dfbd06fa274abe9b0 SHA-1: cd782f8639ec88653aacc1689b37084afe2ac289 SHA-256: b641f2cb006fdf5998c1ce59cde023bd54b54e9554fa5de9b3e9d34eae841df3
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6999b7ebba---89389150740.pdf In PDF document text
    • http://driscollandgibson.com/images/edit_images/file/20929669503.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/43738070443.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16072ad987be44---wiwaninevokulatuvo.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/4ab96d3d119be240da8434d978e6f557/26419924127.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b77cac91af5---zegira.pdfIn PDF document text
    • http://ubest.ru/images/file/12412518859.pdfIn PDF document text
    • http://qctc.vn/upload/files/tipalikubobor.pdfIn PDF document text
    • https://northcoteplaza.com/userfiles/file/70151295707.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/torawajamidonogizagebuva.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7d6a8865d---48351134828.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a65c171bab4---jakevijagililawodarabi.pdfIn PDF document text
    • http://patokapugsnkisses.com/clients/61143/File/fivowasigumalanomukagiviv.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/268a84cf2ecad860ce577703b07d576f/nozobeduwipizuz.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/63598983093.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/06/files/210623213848.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/d2d82acc718f3557f6b96462e5b9122e/lobimirisofumebi.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160962c2be8b63---15744658094.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/b993cdefc31a97fabb429c20bb1d970e/45158462229.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210605_AEC0C582D0B925CD.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/zanuvebebanajujezaz.pdfIn PDF document text
    • https://stbenedikt.ch/userfiles/files/satosamasul.pdfIn PDF document text
    • http://amphorabeautyclub.com/campannas/file/boxidot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=bear+png+clipartPDF 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_off00011cdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CDF 10312 bytes
SHA-256: 7ab98a837925583aea74a1b9e646b7fe2f58c6d04edac48009faf7ddac45824a
font_01_sfnt_off00013430.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13430 17380 bytes
SHA-256: 51b0ba9af9b5e10c147ee274f001d6eb58cd14a2e39b8fd685201bc160f8e284
font_02_sfnt_off00015fe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15FE1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1