Malicious PDF — malware analysis report

Static analysis result for SHA-256 545d80acfac04da8…

MALICIOUS

PDF

81.9 KB Created: 2021-09-03 21:28:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 33bf617ce42914acd9e8b86ef5a3c334 SHA-1: 3ffbfbd1e091c5fe602dce89f2fba98eff043bec SHA-256: 545d80acfac04da8ece5949f984400ebdae65ce20370537ecd7661de9afd3183
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file exhibits characteristics of a malicious link farm, with numerous URLs pointing to potentially compromised or disposable hosting services. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of many unknown-reputation URLs suggest an attempt to distribute further malicious content. The ML classifier strongly indicates maliciousness, and the document structure, while not containing readable text, is consistent with a lure for downloading additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://huntic.ru/uplcv?utm_term=tp-link+archer+c20+ac750+user+manual PDF link annotation
    • https://ms01bet.com/contents//files/90399961336.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/24015999263.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/sbboj209jm9658jml5akinre46/makewipewag.pdfIn PDF document text
    • http://riviera.az/userfiles/file/10040827361.pdfIn PDF document text
    • http://ibb-online.ru/f/file/36475628345.pdfIn PDF document text
    • http://sostrevalli.it/userfiles/files/806787886.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c16ef19b0b8---85955898895.pdfIn PDF document text
    • https://camelcarpet.org/d/files/fejeju.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/26336564559.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/16102e2b8a67e1---78668484503.pdfIn PDF document text
    • https://machnik.net/ckfinder/userfiles/files/28201230644.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/83880504078.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/megifodenipakudir.pdfIn PDF document text
    • http://nesthomes.in/userfiles/file/42715910883.pdfIn PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/32193943686.pdfIn PDF document text
    • http://manisafar.com/basefile/marcosafarir/files/sezugo.pdfIn PDF document text
    • http://sparkpro.lv/content/file/kezulawegi.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/t1dn783nhpl1k9008q3o4kq14p/rofepedamegijivaraxu.pdfIn PDF document text
    • http://traktorpulling.de/ablage/userfiles/files/jevevaterorarafekiwenu.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/77166547958.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16085e62f20de3---gatofasuvufunonowitawelev.pdfIn PDF document text
    • https://premiumtrade.ro/ckfinder/userfiles/files/baligufenamozasejuwiw.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160928d2d97b9a---nulanebefitipazove.pdfIn PDF document text
    • http://rebornfair.com/FileData/ckfinder/files/20210614_34E51B45548017A4.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1630428395.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_off0000cf29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF29 11036 bytes
SHA-256: 454c971021e97c48a6c3b503bb6a0acd7053bcea63a7c5d4934bcfccd8f6d038
font_01_sfnt_off0000e8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C5 21760 bytes
SHA-256: 6872e791d7b054220effd3e88f3e1e7f979748c1b5ea8fd835bb8c96598a76a5
font_02_sfnt_off000121b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1