Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb93d854fbbef0c2…

MALICIOUS

PDF

79.8 KB Created: 2021-10-19 15:56:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9467c1b04e00875576a7db2da3a74ec8 SHA-1: 8fdebf4c7749f477511fbf0c4b6f569a426c419b SHA-256: fb93d854fbbef0c2e71ea3729d0e2dc725f5edee8e039287a66bd2428b3fb45d
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of a link to a compromised WordPress upload storage further supports this. No scripts were extracted, and the document body was unreadable, but the URL analysis strongly suggests a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://dobosugyvedkecskemet.hu/userfiles/file/14785001371.pdf In PDF document text
    • http://parmalab.it/userfiles/files/gekusow.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/tefugiki.pdfIn PDF document text
    • http://yztools.com/images/upload/File/rafan.pdfIn PDF document text
    • http://bangladeshceramicsociety.com/uploads/editor/files/lukipufamepakomewo.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/somilanofinuxowijovanotu.pdfIn PDF document text
    • http://a2kat.ru/userfiles/file/sepusoze.pdfIn PDF document text
    • http://020tzs.com/baige/images/userfiles/file/gegar.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/kejosotizamagexewidakivam.pdfIn PDF document text
    • http://sieuthihatgiong.vn/webroot/img/files/jodewitisi.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/56726663935.pdfIn PDF document text
    • http://xn--2o2b17g32e8xisqq.com/userData/board/file/58135793994.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16163e6c9e41bd---modaxofivol.pdfIn PDF document text
    • http://atdawnwelift.com/userfiles/file/delutosa.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161559b89c25d8---pazotevawa.pdfIn PDF document text
    • http://candemdientu.com/Images_upload/files/22075451761.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/92757904881aaaa52498d32b38880078/74189584381.pdfIn PDF document text
    • http://mdtrend.hu/files/file/sowufamarakobivirigifo.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/xexoxuk.pdfIn PDF document text
    • http://sloplast.com/userfiles/files/goroduweg.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/20110228972.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/oscUj7J0Gjw/uplcv?utm_term=how+to+apply+passport+online+step+by+step+pdfPDF 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_off0000d2e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E4 17484 bytes
SHA-256: f40ab1fc22d4556c41bfedbeafc1adc5d5d4580e79e35a67fe202d7e35ef29da
font_01_sfnt_off0001007b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011892.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11892 10824 bytes
SHA-256: 98fe44fed20f41b2a5f083b32cf60fe210a6bef8073462f4b68433b071c68e62