Malicious PDF — malware analysis report

Static analysis result for SHA-256 0912f4eff2b2a62d…

MALICIOUS

PDF

70.6 KB Created: 2021-09-25 05:07:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 33e966115ae9a70f306b64404b9c8f8e SHA-1: 59ba5b0b840eb67532b96d5c4638f9b858edc15f SHA-256: 0912f4eff2b2a62d009d1488abbcfad0c5c3076581c8a8ddfeeb2c649dfa323e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm the malicious nature of the file, likely serving as a phishing lure or a distribution point for further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://synerhu.ru/uplcv?utm_term=ad+blocker+apk+premium PDF link annotation
    • http://www.radio-kum.si/data/files/zirusoxu.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16145463f402d7---98012895074.pdfIn PDF document text
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/19480785146.pdfIn PDF document text
    • http://akiisushi.com/uploads/files/vivefebakuxazuvad.pdfIn PDF document text
    • https://toyotaautobody.com/ckfinder/userfiles/files/95980184978.pdfIn PDF document text
    • http://smingames.com/ckfinder/files/5849849231.pdfIn PDF document text
    • http://agisma.ru/files/pages/files/77512496285.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/vapixib.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210913_B4EF42F02978683C.pdfIn PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/noximejebutelukopawew.pdfIn PDF document text
    • http://plncse.hu/php_data/file/fupesonasijofazedofove.pdfIn PDF document text
    • http://cserepakcio.hu/xdata/file/luwarixapuzepigibedu.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144142364f56---pabazofenatiduxumevi.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/84696099652.pdfIn PDF document text
    • http://rts-3.ru/upload/files/34903623218.pdfIn PDF document text
    • http://ginzaramen.us/uploads/files/36795170623.pdfIn PDF document text
    • https://pagodatalk.com/_UploadFile/Images/file/61305815473.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318368cd00d---93176348103.pdfIn PDF document text
    • https://x-leather.com/radsportfiles/file/43308207438.pdfIn PDF document text
    • https://soechi.net/userfiles/file/59933581727.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/88469822178.pdfIn PDF document text
    • http://safiorida.dk/operatori/userfiles/file/subatuluxe.pdfIn PDF document text
    • http://komodovo.ru/upload_picture/43730060405.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/serefutavumasiramowi.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_off0000b1dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9EF 17144 bytes
SHA-256: 0ebd9ffdc41eaf7fa4e497e9f628634f0374066c7050875caef0661bddf2f07e
font_02_sfnt_off0000f564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF564 10620 bytes
SHA-256: c05afcce58e2034557d45fa5fafe6132147e23448383baa3df322b6e3df42b76