Malicious PDF — malware analysis report

Static analysis result for SHA-256 a021235c9b0a306f…

MALICIOUS

PDF

80.0 KB Created: 2021-09-21 15:51:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b9170669e73d64853ecce75a7685c4a2 SHA-1: eb409aaad425fd93b56f86c2cb05ef5c6b9417b9 SHA-256: a021235c9b0a306fca555746a3cb549a25b60ee4a85d5c9216a25f7ac7a47af0
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which are hosted on disposable domains or compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicated maliciousness. While no scripts were directly extracted, the PDF structure and URL patterns are indicative of a phishing or redirection campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • 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://archism.ru/uplcv?utm_term=viewing+office+documents+on+android PDF link annotation
    • http://www.mustwalge.ee/data/content/files/ponuz.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614526e2684c6---97416538434.pdfIn PDF document text
    • https://mcq.bmtinhoc.vn/InteriorWeb/images/images_news/files/28720109805.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/veson.pdfIn PDF document text
    • http://wienbildarchiv.com/upload_files/files/fulomazutevezuxegume.pdfIn PDF document text
    • http://tiwtactic.com/userfiles/files/70601590870.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/4838118722.pdfIn PDF document text
    • http://avtokit116.ru/!upload/files/kuwozuki.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/vodogawofos.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/sofamilubeputi.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/edbrc8j55mmbnaocsrbeqmtn7e/xisorux.pdfIn PDF document text
    • http://bora.su/ckfinder/userfiles/files/pixevobefivajifuwe.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/60043824946.pdfIn PDF document text
    • http://lmtechsolution.com/userfiles/13317854553.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/82619839060.pdfIn PDF document text
    • http://thewellmanteam.com/userfiles/files/83810051885.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/d66964a3da17b20e6f562427baa84b52/26914179653.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/93543057681.pdfIn PDF document text
    • http://altiro.nl/home/tjerk/file/rujoma.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/534e5f51496246ed86a8e6e7a4ee2229/1718144717.pdfIn PDF document text
    • http://ugrctrani.it/userfiles/files/padavoxilewok.pdfIn PDF document text
    • https://paulogomeslda.com/userfiles/file/nogolav.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614309514cd67---makirekiniros.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1614036793d313---gobizevalagusesatep.pdfIn PDF document text
    • http://sarigol.kr/userData/ebizro_board/file/70411066767.pdfIn PDF document text
    • 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_off0000d6c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED9 16380 bytes
SHA-256: a0268fce729c67d4b9417dc294c8382daa26a918bc3aa2b065274057a920995b
font_02_sfnt_off0001193d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1193D 10928 bytes
SHA-256: 2a595d5aa5a47cd8323da6b9885691f505d361bd2fbbc3a3a2bf6eb8a97de849