Malicious PDF — malware analysis report

Static analysis result for SHA-256 16a35346ca5d3232…

MALICIOUS

PDF

84.1 KB Created: 2021-09-05 08:57:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e0edc5bcecf0c88f2bbe1861c6f72769 SHA-1: a479de48b41ec0da0d993bf9cf64f63180c728c2 SHA-256: 16a35346ca5d3232cf81daf4c1dbf9410389419dd3816e921651268b50b69079
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The document body is heavily obfuscated, preventing a clear understanding of its direct lure, but the overall structure and URL analysis suggest it is designed to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://feriaalainversa.com/uploaded/files/89984029941.pdf In PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607617a145775---60574923302.pdfIn PDF document text
    • https://euforbiabulgaria.com/uploads/pages/files/29801834665.pdfIn PDF document text
    • http://korean-school.hu/hangul/userfiles/file/galixebolerojilezidejuj.pdfIn PDF document text
    • http://esteticka-stomatologie.cz/files/content/file/pulajegel.pdfIn PDF document text
    • http://sakem.org/userfiles/files/zebokolesosoritimegazewet.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/77590712309.pdfIn PDF document text
    • http://tweddlefoto.com/files_contenidos/upload/files/barolefomate.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/xodixa.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/33843900567.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16081b716a2fa4---fisanodebukotukusaz.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1611ba618d7997---dofisawisa.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/3c7d8982716c041047151008de2e3ead/28407126896.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/2e1b5a1794ee096678b21f6d225959f1/jolej.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1d854cef29---32148693222.pdfIn PDF document text
    • https://alistairmills.com/ckfinder/userfiles/files/bikowajofe.pdfIn PDF document text
    • http://armiikrajowej36.pl/public/upload/ckfinder/userfiles/files/81903909546.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/90780746140.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/d20e91b71b1413554f689eafcd47002b/89046389278.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/fexizufosawulokago.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc092e7f24---539871124.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/gifunajif.pdfIn PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-8-25/20210825195628319719.pdfIn PDF document text
    • https://x-software.cz/data/file/tuwejovizakifo.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/kekogutofonuwafetawe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=manual+impact+driver+bunningsPDF 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_off0000e3b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3B5 17512 bytes
SHA-256: 8debec79ebb117066941b62c747b926138ba445814add121dc89cc86dee5eb4f
font_01_sfnt_off0001114f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1114F 11036 bytes
SHA-256: 2a904042d7bf89d6296e13849b0f846ac75aeac252e12dc1df333234512d6860
font_02_sfnt_off00012a8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1