Malicious PDF — malware analysis report

Static analysis result for SHA-256 323f88abf62b9fb4…

MALICIOUS

PDF

72.8 KB Created: 2021-09-16 00:49:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f4a76e987d7b9fe98f82dd81326a9355 SHA-1: 5d5666a798b4c2c5aa8fc8d05975cf40de2a61ba SHA-256: 323f88abf62b9fb4606de765d2ac4310736a68e506979d3d9c3f720924aeb675
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://apsara.ru/userfiles/file/gowakalodu.pdf In PDF document text
    • http://geometramaurotozzi.it/userfiles/files/tiliteto.pdfIn PDF document text
    • http://mrukseo.pl/userfiles/file/kodofutuse.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/37315812182.pdfIn PDF document text
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/pubadutadam.pdfIn PDF document text
    • https://istanajp2.com/contents/files/46579651638.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/73390903601.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/gavekiwukamoseroji.pdfIn PDF document text
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/33617226501.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/ed11eb00336ccf586ef41dee87a828dc/kuzejodegu.pdfIn PDF document text
    • http://www.look4job.gr/images/_user_na/file/vijabupagepuwixufiro.pdfIn PDF document text
    • http://egyptlance.com/userfiles/file/riteruvavemamo.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbba207c4b---gotomejidofebotopujelida.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613453e24fc94---97955550836.pdfIn PDF document text
    • http://funagamex.vn/PhuongNamGroup/userfiles/files/ruzepegovovugi.pdfIn PDF document text
    • https://ngoctraithaibinhduong.com/uploads/news_file/66313769060.pdfIn PDF document text
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/xefopebisesalajenon.pdfIn PDF document text
    • http://naviway.su/upload/files/mapodanafetujozowazut.pdfIn PDF document text
    • http://centronegozi.com/public/zijanexomadewasilebejini.pdfIn PDF document text
    • http://mellorymotors.ru/admin/ckfinder/userfiles/files/6978736217.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/32364340739.pdfIn PDF document text
    • http://twilaw.com/files/files/woson.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/90690352735.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613da74a2cdde---zudapefuxoratiko.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=monster+house+espa%C3%B1olPDF 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_off0000b90b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB90B 16860 bytes
SHA-256: 22e60b039ac23fd37719aa5dd8e6f64485e5f9e5d2a14d91b332ca4a1de02a5b
font_01_sfnt_off0000e455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE455 10556 bytes
SHA-256: 7762284740ddc1390c63d5f650417967162eacba770f466a3c28d79897a39f47
font_02_sfnt_off0000fc20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1