Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a6bd680c1d49c7e…

MALICIOUS

PDF

88.0 KB Created: 2021-07-16 18:52:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 90c99ab33e98ebf3291e1f9b800a8e26 SHA-1: 69f3fea6c535fbda596ad5ef48ac76155f63ed22 SHA-256: 3a6bd680c1d49c7e66a455e8bef2f4a674fabc81c080781ecc2dcac29f0ca72b
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to exploiting users through these redirects. No scripts were extracted, but the structure and URL analysis are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://anhuishangbiao.com/upload_fck/file/2021-5-2/20210502065806384320.pdf In PDF document text
    • https://mszukam.pl/dat//file/lexigizevu.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/4b387cf8c6d781cabcf3f18587e72dac/xomobeg.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/8p2tpm6p2n0vb05q71pt0gbtto/medat.pdfIn PDF document text
    • https://triosms.com/userfiles/file/10297529038.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9161992fc---fuzopamezikegurifak.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/3386566641.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/444b371d20d2100470ba329f7994b0ee/49359291658.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/gokozemuvib.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/r77rg41qqub1akdd1ivt836d82/topol.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/sefk2qqjo5omektmu8gi2lhai2/zokerulafudizivagoperine.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078d71d49852---fajidateginuzesoninesuwew.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/jikogax.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/79880369491.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/fa39c139b2a974bb1d2890be0ea0d786/rataluvujusuvudeles.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce495300ba---jixezaxupoj.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/ff2029232f30d9e7a63e7de0eae92b32/23799879493.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/7df3d761b1c2a624475dd379f7dfc7c7/juwupuvopademinavatekuxu.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/98akitncifqtr5eqa60ls1d9og/44793917692.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/123232865460948b5c74aae.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/mopuvujalulopawelotetu.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa79c9c2e0---7357490285.pdfIn PDF document text
    • http://winfielddeli.com/ckfinder/userfiles/files/vosekotog.pdfIn PDF document text
    • http://paulsaperstein.com/userfiles/files/46968930493.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=alternating+current+mcq+questions+and+answersPDF 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_off0000f210.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF210 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A22 18068 bytes
SHA-256: d717c3f01544e78faa0d7e513cafb1e6bf2fd31782c01b97541f6b401ef8c8c9
font_02_sfnt_off0001394b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1394B 11024 bytes
SHA-256: 41cd696576f109a7f051ce60db9475b3987f834f6e0cb49c5d646c2cee90d0bc