Malicious PDF — malware analysis report

Static analysis result for SHA-256 a43876e04faccc77…

MALICIOUS

PDF

88.1 KB Created: 2021-09-19 03:19:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 436a5d21760592104e883fb51c9e9230 SHA-1: f0ae10669c7615a9b030fb2c7b6c8ae9699b34fc SHA-256: a43876e04faccc7731b612d45f2c7c40aaf171271529aa5a54f419469ce73541
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm heuristics, indicating it is designed to redirect users to potentially malicious websites. ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious classification. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://medvor.ru/uplcv?utm_term=ullu+movies+online+free+watch PDF link annotation
    • https://livre-art.com/ckfinder/userfiles/files/tefigedupoku.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/45102007222.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/26783127226.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/6208277273.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/fitudexolovesepe.pdfIn PDF document text
    • https://lotte-ppta.net/beta/assets/file/50626642417.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/zimurusimesupikuwokeb.pdfIn PDF document text
    • http://bangdientunhk.com/upload/files/wirefabew.pdfIn PDF document text
    • http://auburn-companies.com/userfiles/files/terowobavovilejumum.pdfIn PDF document text
    • http://ayrh.internet-match.com/upload/files/80434378523.pdfIn PDF document text
    • https://buddhaart.in/userfiles/file/pegitegiru.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/161444c3fa1d92---motinux.pdfIn PDF document text
    • http://digitalpolicycouncil.org/imagenes/file/29499881673.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c9a7f3709---16290648987.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/gojepetunavuva.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/dedoritof.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/givozugar.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/75277201958.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1627c32d6---78666957431.pdfIn PDF document text
    • https://schmitz.cz/res/file/zevidik.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/zalunipidasakorof.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_off0000f4fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4FB 10860 bytes
SHA-256: d9e6c015798bfd0278c3d35373f2f57491f2ac6cc490f2f124182762927036cd
font_01_sfnt_off00010dee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DEE 17596 bytes
SHA-256: 00b4ef71ee11dbdca2e8337d1e573261634644800af5e826d9f84769606d5f40
font_02_sfnt_off00013b23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1