Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff8da531cd4ae063…

MALICIOUS

PDF

92.6 KB Created: 2021-07-16 07:52:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6e924a60782057fe3c90dbfcfb409ec1 SHA-1: fccf244b0db1b6b2ea12d98946c667fea8d272e9 SHA-256: ff8da531cd4ae063f5f400afd3e033e59476f8c7bc6d4bed7c93d40dbac07154
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the structure and URL patterns are consistent with a malicious PDF designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/0e781cd83b2e8fd529adc0d84c18e215/41944148608.pdf
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/55abde645b89158d976d42e6db44e555/31588133629.pdf
    • http://icsbc.ru/fuploader//file/66743462042.pdf
    • http://vitalenzyme.com/uploads/fckupload/file/2091622877.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607925f68abc0---pefuse.pdf
    • http://clarklawtexas.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/venesadifetofa.pdf
    • http://nsdadventist.org/FCKData/file/jabidodixiwefilafekuga.pdf
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/6219bbd9a712fbfa8907a938812a5b1e/vofipa.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/5f89fddd7e5b834b45c836eec8ab94db/revedefiwajipafupofufabu.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/c2o9304284lb0fs348krna80vm/fesubelejufalu.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/8fc3f0dd97fa31c0e78166b9b930a9a3/62388817501.pdf
    • http://kapelski.pl/userfiles/file/zofulosaf.pdf
    • https://bucatariizidite.ro/printuri-fi/files/fugajexupovodifaman.pdf
    • https://argekaucuk.com/nbg/upload/files/44476516205.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607c707a7f419---43464644439.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a8ba0bd1191---23441050409.pdf
    • http://k-yoga.org/file_upload/spaw_upload/file/20210626081955.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e842850327---84196536987.pdf
    • http://hjtech.org/admin/upfile/file/semidorox.pdf
    • https://makeswebsites.com/clients/c/c8/c8c605999f3d8352d7bb792cf3fdb25b/File/rujemobunamukejulunaxima.pdf
    • https://equantumconsulting.com/files/files/81236594961.pdf
    • http://sys-svinding.dk/userfiles/file/vikokog.pdf
    • https://kasihpaham.com/contents//files/kumosap.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/4onopjt2arhqc3oikmqt4g7ubc/nezuf.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=odds+on+ncaa+tournament
    • 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_off000104d7.bin
ec9c8b501075879cc2211e1aa4decf8fa5c0b8d5b3d8a0c6e9e2c8fc08ae3adb
pdf-font-stream PDF embedded font (sfnt) at offset 0x104D7 18640 bytes
font_01_sfnt_off00013569.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13569 16792 bytes
font_02_sfnt_off00014d80.bin
6b386314abaaf55a23abb44f293fcf1c5967a630b0a0163dab1b0386d9d9fad0
pdf-font-stream PDF embedded font (sfnt) at offset 0x14D80 10520 bytes