Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f710fcb247cbf86…

MALICIOUS

PDF

84.3 KB Created: 2021-08-18 11:49:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e6a44a7658c55f4e58453e2724fe6077 SHA-1: 5278ceac217eae3e49b5fc084d143bc159bd9316 SHA-256: 7f710fcb247cbf865f45092afcaa6f7146d29b772ef8330168257d21698feae5
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or SEO manipulation. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pepsima.biz/files/file/dolusekavi.pdf In PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4ac297e0dd---regogazubepet.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3a20bbc691798780ef66489c372a76c1/depedilenifi.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088ac2707923---buzoberov.pdfIn PDF document text
    • http://yorkiematch.com/clients/6/65/653dc45b8f6063886304ac4260dbb99c/File/17352270398.pdfIn PDF document text
    • http://sibmetiz.ru/upload_picture/lezamimoludex.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/xaxufizakajupilodazon.pdfIn PDF document text
    • http://hkt-optics.com/hkt/images/userfiles/file/17128777041.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160731e906ac3d---20018152285.pdfIn PDF document text
    • http://bean2beenefamilytree.com/clients/60578/File/wilopiwib.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/lilunusizubisifize.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a76004cc4---nikijipulezorezepotezo.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/5adb7fdf3e2eed3e8808e93afcd94d6f/66671779575.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5bde0af552---47032977029.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/5qvn6hj1vnlkvsk1elq13c1qo7/85490308636.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d81ae39b80e---komawif.pdfIn PDF document text
    • http://biosite.ru/images/news/file/pevekipe.pdfIn PDF document text
    • https://www.varisistanbul.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5e89f273c---dipiludatisem.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5739f3cf6---97383043303.pdfIn PDF document text
    • https://avvocatoboretti.it/file/28332669420.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/fudosoxuwikopan.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d19f6929a6---7998821551.pdfIn PDF document text
    • https://studiorampinelli.com/file/62134403753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=why+is+my+zagg+keyboard+not+connectingPDF 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_off0000dffa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFA 11172 bytes
SHA-256: 4e395f43b08fb3449ae5ae4a7f23a1798bd509f29a86e52028632be8b7c13d91
font_01_sfnt_off0000f9c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111DA 18112 bytes
SHA-256: 0085bc5e3d16650ec11d2039c9148e4ee304677523cd45fadadf1f94238bf81c