Malicious PDF — malware analysis report

Static analysis result for SHA-256 1539cd628f4aa9c5…

MALICIOUS

PDF

80.3 KB Created: 2021-09-04 06:30:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fc31ca79ed0edb37a33f37994276430b SHA-1: 4efceb2b87e68d469a9a3deeea6b0bd7e57cc644 SHA-256: 1539cd628f4aa9c55bf1c384fc7e0a56e3ba5f45d07ccfe7a12dde839563911b
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, containing numerous URLs pointing to compromised WordPress uploads and disposable hosting domains. These links are likely designed to lure users into downloading further malware or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082d31738b06---25750460294.pdf In PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/jiwilig.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/31953461821.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/57942872207.pdfIn PDF document text
    • https://dascalita.ro/app/webroot/files/userfiles/files/18647093602.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/zepawuluvafemivuzoru.pdfIn PDF document text
    • http://srsheicha.com/uploadfile/file/kudabugoxevuzoju.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/58bj5ufub7b0mo883gn3oki0kv/17142142178.pdfIn PDF document text
    • https://greenways.at/userfiles/file/60850287279.pdfIn PDF document text
    • https://gtselect.fr/ckfinder/userfiles/files/57621707275.pdfIn PDF document text
    • https://mimpiindah1.com/contents/files/nebiwadebakefoferejanabi.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/129otoigona19qahs0c2jtf786/39235034212.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16095d30e837d7---lazutadi.pdfIn PDF document text
    • http://schokobrunnen.com/idata/38245252163.pdfIn PDF document text
    • http://porpora.eu/imagenes/imagenes_contenidos///xupuzubozo.pdfIn PDF document text
    • http://ozari-ua.com/files/file/razevabiva.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210609/0514559443.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160a373609a710---33010417013.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/3100578088.pdfIn PDF document text
    • http://cluboutletmoto.net/campannas/file/zevidurava.pdfIn PDF document text
    • http://eotp.info/sites/default/files/fck/file/kepejomimu.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c173916b2f6---85326035898.pdfIn PDF document text
    • https://yar-net.ru/userfiles/file/bunufijot.pdfIn PDF document text
    • http://marketherballize.com/ckfinder/userfiles/files/lilafikizuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=word+mine+book+pdf+free+downloadPDF 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_off0000d384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD384 10704 bytes
SHA-256: ef58f2bbb8abd9e651a759a223f0e705178c6430df597a99d3b0d9899e6d6ec8
font_01_sfnt_off0000ebcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCF 18284 bytes
SHA-256: de7d25cf46ced2f7c56c68b234f892381d46b4ad3376c9837e5dfb53905be3f8
font_02_sfnt_off00011b96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1