Malicious PDF — malware analysis report

Static analysis result for SHA-256 431812598ea99d61…

MALICIOUS

PDF

72.1 KB Created: 2021-05-29 16:23:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: 9a16ca9c27f96075985bfd6cf735cf54 SHA-1: 551602ce95d0927df0ec30e27ac1fc6a53d59ec5 SHA-256: 431812598ea99d6117906fcf348f30b2e6065650423bd2d4bd2d399261ce8f61
154 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites utilizing the Formcraft plugin for file uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm on disposable hosting and the use of UTM parameters suggest an attempt to obscure the true destination and potentially improve search engine ranking for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9394

Heuristics 5

  • 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
  • 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://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1606c65b4ccbfb---jipavimejen.pdf In PDF document text
    • http://webcertain.net/contentupload/fckeditorUploads/organization_/file/7849481035.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e8a4872729---livugoxupe.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609675c9a49ba---88863009077.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/d7il3hvleopsga275s1c5do4tm/piwowabokofozax.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4fe37a761---rezubuxaponik.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861f720fc4f---wekovogefinipo.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/e7485b00aa1cc5be2a4f7e9a3a210cbe/4678141326.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/2697abc54cdf8b1127cd9e31ede1706a/sasexigezebano.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16080bb7fcfb62---82723908294.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/cdfad7e991b184889ccba3beaa3d4cc2/65381316962.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b4f8c5c4b---54472514262.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eceb4d87b0---bafiw.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1607b95e3155ad---poxilama.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/qsbvct2mmvu3ar5muvuch4c7c0/wiwaguzadowup.pdfIn PDF document text
    • https://tigercabinetry.com/wp-content/plugins/super-forms/uploads/php/files/f815a156c770c41f284d5c39b4ba6436/vitarebepetofiregagibut.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0ae0b3644---zapofuzolawunazesenu.pdfIn PDF document text
    • http://lokale-uzytkowe.pl/uploades/fckeditorfile/xomebo.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1fcb7e12f---fuzes.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=quipper+video+apkPDF link annotation
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e25e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE25E 5504 bytes
SHA-256: d1612fd2c3f2a453eade2bb97f51797d65bf8200cee4321330eba64291fea84f
font_01_sfnt_off0000f583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF583 4928 bytes
SHA-256: deeffe1df0802c28f835531865edc92437ac90f5c608cee2f8cb6d802ca0aa6a
font_02_sfnt_off00010654.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10654 2520 bytes
SHA-256: 9c0bdc5b6922f015da375b0f6e239734eae11dddeba4f06ea6fe26239dbf29bf