Malicious PDF — malware analysis report

Static analysis result for SHA-256 a659dbca63963b1b…

MALICIOUS

PDF

88.6 KB Created: 2021-06-30 22:58:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c060dcad2360b816ba685eeaba490baf SHA-1: e70e5eb1e5c8f3ef03fde1887d05f349a7d20ec4 SHA-256: a659dbca63963b1ba98224be0a78f8cf9b945dc77db71b50cb800d8f8e13a65f
96 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 WordPress sites. The ML classifier strongly indicates maliciousness. The primary attack pattern observed is the use of a link farm to redirect users to potentially malicious content, likely as part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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://haps.company/wp-content/plugins/super-forms/uploads/php/files/qs3du6863l28vf0l36pav3kvv4/64937915155.pdf
    • http://solarexperten.ch/fckeditor/editor/images/file/34099229942.pdf
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/fcb771a6ccb00b13431a685365d8346e/12264046966.pdf
    • http://baohanhranghm.com/upload/img/files/41945228568.pdf
    • https://arte-salon.ru/upload_picture/13955699882.pdf
    • https://italvaping.com/file/83173044943.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/foif3c93s0u57kg6obaakmsgp1/gadadubazesegikixe.pdf
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/86512ca91d56ed5240e9288a85e73156/gemosujokojekexe.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/rk9vqjrougkfivofdla3mp08ld/63605361804.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d864d377edc---12380527441.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160748a0c99fd0---28433948876.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/l6iintah8ko42tpjr0hqu8nsqe/gawuso.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085b85410fd1---lemexujurodazekukewif.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/ad7fae6e5cf0434c2266a5edf3ef8520/27825590226.pdf
    • http://rasmesafar.net/basefile/basefiles/vugovexurekakepem.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/6c69u90vd7leu62upi3011ntco/wefefitetopaludazokewe.pdf
    • http://saigondome.com/uploads/userfiles/file/mijatinenagodiw.pdf
    • http://asfalon.com/__files/file/wonumafo.pdf
    • http://talleresjpg.es/img/file/fasufugoxejasago.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071ba9cdb94c---92691840723.pdf
    • http://chromoink.com/updates/file/37045960475.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b4ae56459ea---duzizi.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c978b529faa---77147724085.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=among+us+cheats+free+android
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da28.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA28 16792 bytes
font_01_sfnt_off0000f23f.bin
ef3a17a7e00f8f24155f7c240e21bc39be49e19f6eae84ebd8762cbe3c41c212
pdf-font-stream PDF embedded font (sfnt) at offset 0xF23F 10960 bytes
font_02_sfnt_off00010b51.bin
f5572e1b5c25194cddd5bbfb3d58e44c49dc98a8c678be759d186c088e0f41ca
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B51 18060 bytes
font_03_sfnt_off00013841.bin
9973d70b28b27ce844da1639052a77654f521be3a31443e47b61b57c2d9c0496
pdf-font-stream PDF embedded font (sfnt) at offset 0x13841 17600 bytes