Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9cf0f0e65874528…

MALICIOUS

PDF

87.8 KB Created: 2021-07-18 05:30:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 854dbe2cc17fcf110a13269d68a9e0dd SHA-1: 1ed35cf12baf6c7d4d93b61c25b74916bb5b2360 SHA-256: b9cf0f0e65874528e26b82bc711a3a7885d0da20c2ff5b19961763cc88c66ac6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, hosting numerous URLs on compromised WordPress sites, likely to redirect users to phishing or malware delivery pages. The presence of multiple distinct hosts and the use of UTM parameters suggest an attempt to obscure the final destination and potentially track user engagement.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/0j69h4d65leu4efnflgmgbq3m0/zebowenuwugexar.pdf In PDF document text
    • http://cuhs1981.com/clients/8/82/82ca37c076ec4232796cb58ed009bb3a/File/kozonenaninoxuzobukeru.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/160f0fc75d0654---tobukanavut.pdfIn PDF document text
    • http://ayurveda-shiatsu-qigong-nice.com/upload/files/ferinevugor.pdfIn PDF document text
    • http://soul-program.com/clients/e/e8/e84723a0d254fbc5507aaa4bd1967541/File/29606958019.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/fd68fa7a797b56b1bdb02a0fa10522e6/sodiwoluw.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/3137c53fac9b58ce2bf2d368e24c3af3/27554029406.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5d47f0db2---11250544556.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/51856116842.pdfIn PDF document text
    • https://leo.tw/upload/ckeditor/files/rokejikajedolezajoj.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/s5uijfrfn1dcqr8767ucjehg4e/91468864972.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/jcssa2p17s8i2lj4lv5a1tau55/kimulitevigaxuvi.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/aalek6s89em9fkr0f9ncm2qsg6/45731964015.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/3fe313e68ce28c48a54b973088e5d880/21962024265.pdfIn PDF document text
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kawaxujufatexaz.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160965c30b6fca---56885475590.pdfIn PDF document text
    • https://nadinerogger.ch/userfiles/files/32426482447.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e4f0e1eb24---tekinegojup.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/87578956958.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce0fcc74a9---xijev.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/6e6d5e64c0aa4143b794cbf04c3a9209/19178210794.pdfIn PDF document text
    • http://alessandrobelleseveterinario.eu/userfiles/files/fabozojim.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/2503c4e356473b5cc3dcf531c0cee59f/1878370939.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607e942ccd34e---18867629098.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/c65d60c1de782deddc36597160648ac7/91120925372.pdfIn PDF document text
    • https://patoman.ro/ckfinder/userfiles/files/rasobalezabiso.pdfIn PDF document text
    • http://szentistvanpatika.hu/upload/file/likirixojoxuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=reference+upon+request+meaningPDF 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_off0000f04b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04B 18316 bytes
SHA-256: e4bb2109b6f6fa2b7d45b3b803723bf2b956f4dacb33ac71241c7dcf2926ddf5
font_01_sfnt_off00011ebf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136D6 11068 bytes
SHA-256: 4ecb72f6005cc122020811767891a96f229cc8c0dbcf03e3fea0434182e144a0