Malicious PDF — malware analysis report

Static analysis result for SHA-256 211ccceb3620cca1…

MALICIOUS

PDF

71.7 KB Created: 2021-06-25 17:32:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 63ae367edf9610f18c9059154dc63893 SHA-1: 8571bcf6dcf0e8356ca4f6540510d394c3e1d690 SHA-256: 211ccceb3620cca1bb23b2207a062a750ab95cee2710dba1a6146d23246eb356
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of links, many of which point to compromised WordPress sites hosting other PDF files. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607160304260a---63495278909.pdf
    • http://richmediahouse.com/admin/uploads/file/mugevojupasatosotij.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee8f248245---bulekeliwupefojarizuvipaf.pdf
    • http://royalproductsonline.com/userfiles/file/18465644680.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609087803fd73---8174802898.pdf
    • http://piotrkowska77.pl/zdjeciafile/patulewezurujoju.pdf
    • http://scro.ru/pic/file/16957170208.pdf
    • http://musorcentrum.hu/files/article/file/darasemiru.pdf
    • http://absolutelyneon.com/userfiles/file/fivixevawamegodewejugan.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/70a226e4b37a3bef9f7582edc6996d03/51119753350.pdf
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/6c69e828a1a717d9361d18d22dabbcdf/nifowisa.pdf
    • https://craftsmancuttingdies.com/wp-content/plugins/super-forms/uploads/php/files/1c407bc8390d5ad73f18a5781f27cbfb/29268144684.pdf
    • http://barbusci.it/maisUserFile/file/fenujigivoxunor.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/2g7pih80ora9oo4ph00udu36p6/23140754217.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/imal2j6gmq78tujriu170e9105/97903751302.pdf
    • http://grupopiscis.com/upload/files/wexumevixe.pdf
    • https://karapinarinsaat.net/userfiles/upload/file/gobodewasaresipu.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c348bd6fab---91438312942.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4beigc0p0ndrilp6ar7i4mb994/wadimesitoripi.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607285a936b30---75930213968.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608582129049a---54313761823.pdf
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/96b1fcf054b6a3d0c7b44df65185daa2/rawupoluforivolego.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/059609329960b836f217d629f4c31ec4/54058063473.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e29e69ad82---mafur.pdf
    • http://yihui.name/knitr/options#chunk_options
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=r+in+probability
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b89e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB89E 16792 bytes
font_01_sfnt_off0000d0b0.bin
126d4ddb34569e54d65f6fccaf7c6038d2627132c5ae413ab2d0dce179c4ab63
pdf-font-stream PDF embedded font (sfnt) at offset 0xD0B0 16216 bytes
font_02_sfnt_off0000fb29.bin
662ab9c680969cb82d00503f00ee4c3f2df0a9ea36ab8c2248bb7e0bdb658ceb
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB29 10244 bytes