Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a6696a3c4e49107…

MALICIOUS

PDF

91.0 KB Created: 2021-07-25 15:08:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 16e777911b900abe46ba6a804d654e6a SHA-1: 8461a73ec44de168225ebda99f69d295ea2f3660 SHA-256: 5a6696a3c4e491079d86727af652debfc2f332ed198441f9da6d7446e4cf6db7
96 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to numerous compromised websites, many of which host other PDF files. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to lure users to malicious content, potentially for exploitation or further malware delivery. No scripts were extracted, and the document body was unreadable, limiting the analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/s55dmhf71mtgj43lhfoherp3qm/sepagob.pdf In PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd62628165---79000077832.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/1def45ef4c2417661755ea19a8d9e824/xapavegunobutipowezabawaf.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/lowixukojidipiguxadijow.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/jdui65rbk496scu3r2gpn1f392/93879370834.pdfIn PDF document text
    • http://fujiya-burbank.com/uploads/files/6586168092.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607239f462f3e---narevik.pdfIn PDF document text
    • https://dodatnagarancija.com/userfiles/file/77676480227.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/160730cd215a17---4361210040.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/e607b70a2e00447d8037d5bf29da47b4/32298248207.pdfIn PDF document text
    • http://yorktownhs1987.com/clients/57482/File/66203114913.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/fd742c5d4550f5bee954c7e809927e1d/dutipenoduzowerapoja.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7dbae6db1---dojumopuki.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/3f1e1819e433a36a4038d2446059b679/dipasotasepilokiloxape.pdfIn PDF document text
    • http://www.salac.cz/ckfinder/userfiles/files/gebuxobesala.pdfIn PDF document text
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/a296db156a5e233e98336328643b89ad/sajupen.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6dede94dc---tinugeribixibinikatix.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/dofim.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/a7a0a2233a14097ad5b33e71bf01e304/mogitelajakozawura.pdfIn PDF document text
    • https://beruanglucu.com/contents//files/kurifilexitizuzadobawum.pdfIn PDF document text
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/tuwojamurigi.pdfIn PDF document text
    • http://creatinglifeoptions.com/userfiles/files/jivibugusoxu.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b81a176262a---86733711684.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=como+combatir+los+piojos+y+liendres+en+ni%C3%B1osPDF 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
    • https://medlineplus.gov/spanish/headlice.htmlIn 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_off0000fc3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011454.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11454 11296 bytes
SHA-256: 27c1056fb2d150ca7bf6112525c8cb15a0ec87d652f1b6667d9e969c9cfc2af2
font_02_sfnt_off00012e5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5D 17856 bytes
SHA-256: 2e597aaefd176d28255458413c7fd0937ba70e5a44df9f51bcb12300ce008a3d