Malicious PDF — malware analysis report

Static analysis result for SHA-256 23111d6eb3b0168e…

MALICIOUS

PDF

73.7 KB Created: 2021-09-18 21:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 58d4269b44163365ca62aabca95d2a3a SHA-1: bd5596742545d013b9fb0d2f6597e5350d6661bc SHA-256: 23111d6eb3b0168e712b70a012a724218540930fda5414d6f2a20f6105b855c8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous links, many of which point to websites hosted on compromised Content Management System (CMS) upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary attack pattern observed is the use of a link farm to direct users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9939

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://gardatrans.com/content/Files/devowof.pdf In PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/211d6f78632929334b5d4c0084e4baa7/goxesevaxifipojejapivinar.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210908003805.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/80353820057.pdfIn PDF document text
    • https://efficientinfocomm.com/ckfinder/userfiles/files/watoko.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/17009858961.pdfIn PDF document text
    • http://winkeleninzundert.nl/uploadimages/files/kuvesimuwelodonebusojite.pdfIn PDF document text
    • http://grupafurman.pl/!mag2011/userfiles/file/vogogefijikeza.pdfIn PDF document text
    • https://www.domaine-vrignaud.com/ckfinder/userfiles/files/womimudarofenimep.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/susepeki.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e47e6876ee---jufubewojotozotikexur.pdfIn PDF document text
    • https://vitanov.rs/files/kutemitimok.pdfIn PDF document text
    • http://nb-magnet.com/upload/files/30840779531.pdfIn PDF document text
    • https://langumeistras.lt/i/File/66103336873.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/84917886054.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/mizugitatuvimur.pdfIn PDF document text
    • http://cameradungphat.com/uploads/files/80715289761.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9a53c54da---31765103477.pdfIn PDF document text
    • https://i-try.tw/upfile/files/2021/09/03/45392542904.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161338412e99a4---gonopabe.pdfIn PDF document text
    • http://thanhnhomdinhhinh.net/uploads/files/83463294812.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/velelevelo.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16144efbb3a8b6---19313889888.pdfIn PDF document text
    • http://shanghaicruiseparty.com/uploads/file/lolamejefimopixotomomu.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/rab745mkc1pqofrh18k3356n66/paxugupodepisiga.pdfIn PDF document text
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/63438846759.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=number+1+game+of+indiaPDF 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_off0000be48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE48 16400 bytes
SHA-256: 033db17b83b32c0a8e71adcb54be5419fec0b2b689eb053d1afa1334206d3f64
font_01_sfnt_off0000e84d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE84D 10656 bytes
SHA-256: 5c562368cf81f45f0f07903461473fdd3a6a752f74e84e347b8de463338631ba
font_02_sfnt_off0001007c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1