Malicious PDF — malware analysis report

Static analysis result for SHA-256 d621a7f1de5da297…

MALICIOUS

PDF

74.3 KB Created: 2021-09-03 18:59:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b2064e93cc5a660d9381d03858437c17 SHA-1: aa4e812924a3a7c16c5a2f46056bcfca2f7ef31b SHA-256: d621a7f1de5da297a49c547c2b1f85dbce4d35813e56302c7e7a8efacc5c0a2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://burattinojatek.hu/userfiles/file/40411591524.pdf In PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/e676a508a94c5c3711bc161d72a95dd2/26342858810.pdfIn PDF document text
    • http://bptramptour.pl/files/file/80420544201.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ab854b86303---20193835191.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/90422486532.pdfIn PDF document text
    • http://thuexe7cho.vn/upload/files/68971868481.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/75966219637.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/452663b01bcda59900aa3bc51cc08fe2/nugadaregiselaxamun.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/03ebl1ppibkmtdb5nc5bb4ak3v/mupomimojureko.pdfIn PDF document text
    • http://workcoop.org/fckeditor/userimages/file/20210528041543.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160836d4a80f2f---84561013675.pdfIn PDF document text
    • https://indiantalentjunction.com/milan/media/wewawituwapifixumikuzu.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c537c2512c---63523710656.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/36177856292.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/5556ce9717e7165c970bfa989815940f/11447241390.pdfIn PDF document text
    • https://studiorampinelli.com/file/gewumuleja.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/kupisisox.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160763bda6041c---silugosoxuf.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160c4dca1e2c97---56192304653.pdfIn PDF document text
    • https://fotokeramika.bg/userfiles/file/mesinan.pdfIn PDF document text
    • https://ehbo-oostkapelle.nl/userfiles/file/2759125210.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/zedunolojufigotavovore.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/84931817558.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=cisco+multilayer+switch+configuration+pdfPDF 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_off0000be77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE77 16364 bytes
SHA-256: 5414744d7c774d69298324664a28acbcc03e1d0bddbb50a07f7fe75801636043
font_01_sfnt_off0000e889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE889 11400 bytes
SHA-256: e70cd69e8aac4c2a70b3540e26c82d30dfdc6231d005a98226cce1712c76ecc4
font_02_sfnt_off00010326.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10326 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1