Malicious PDF — malware analysis report

Static analysis result for SHA-256 16a5c50742636ac9…

MALICIOUS

PDF

83.7 KB Created: 2021-07-08 11:44:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e7fdfc2c663cf26b419a15e27451789a SHA-1: 55ab61d798e791c7927e39c2c43554a6724eaf6a SHA-256: 16a5c50742636ac9ebf7c1f68b416806331aced4092463b3b3fc524a28f2baa9
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress upload directories. These links are likely designed to lure users into downloading further malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/6c56ae9fa9a0eeb10eafff59124d92e6/rigizulunanulolodolupu.pdf In PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b002b129db3---49287830074.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b79a0f30e3b---25313909978.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/f1475877ca3c86d34009fbf0740f1583/naxikegozoguzusevepezuz.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/45947672970.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/f6973a1a65b6386e24ecd49cb89e62c9/dazegodo.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/17294861e692aed733ff5579c8e7ef65/96027074263.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/lh3fjkb04equdro9s2hg1c9dqo/66150709429.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/a583ca101b04f2cbe27929bf9adaa030/95694773106.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/47139421371.pdfIn PDF document text
    • https://drvishweshwari.in/userfiles/file/fopakovotixovitotogux.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/28857636790.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/82395708095.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1f527a2c6f---54193633129.pdfIn PDF document text
    • http://www.huntsvillepr.com/files/files/99592783953.pdfIn PDF document text
    • http://allg-gyn.ch/userfiles/file/gudemim.pdfIn PDF document text
    • https://cecprint.com/images/file/40814343960.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ba89f641bdc---narukukeniwolotova.pdfIn PDF document text
    • http://studiospazioambiente.it/userfiles/files/kizozigifizegiji.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/f8glhgh0knimmdf35lcr4pdocc/dadoxolazix.pdfIn PDF document text
    • http://www.rotudavid.com/ckfinder/userfiles/files/64361743335.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/upqo3q9lulua3tj7ettl6djpfe/74739523287.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a646ed5994e---11147676374.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777182341c7---vulapepowowukap.pdfIn PDF document text
    • https://bda.ch/ckfinder/userfiles/files/dusozox.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1291a9511---suwusagalusatuwumavuximuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=thermal+power+plant+and+nuclear+power+plantPDF 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_off0000e538.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE538 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4F 10668 bytes
SHA-256: 3a0b1896d2a6494d7ffa0695275cabe44486e9ad33a66e20383f4397b8bc66ab
font_02_sfnt_off000115a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115A0 16912 bytes
SHA-256: d42c23b9482634457e38834bd130ffa08794f3d872ea367f458464e9e9316ffc