Malicious PDF — malware analysis report

Static analysis result for SHA-256 df21877248f30f89…

MALICIOUS

PDF

95.4 KB Created: 2021-06-28 02:22:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 638deeff9da3644bb5801a2095a3d9a7 SHA-1: 2abe6db524e9388e5903ebb910760904b1f11c39 SHA-256: df21877248f30f896ca0c13edd691ea3c0ea2c3a55e92b04ce5938900d4378ac
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDF files hosted on various websites, many of which are identified as compromised CMS uploads. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. The presence of embedded URLs and the nature of the linked content suggest an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/065ad8b0e51b673b239458be21bec66f/59496580765.pdf
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b6346686b60---84004307017.pdf
    • http://csptech.net/admin/userfiles/file/62950895096.pdf
    • http://ambulatorioveterinariocigliano.com/userfiles/files/polikixalu.pdf
    • http://driver-jazda.pl/upload/file/5056223885.pdf
    • http://btc-ltd.com/upload/file/55688301189.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea4583f48a---norokuzowazulijasezavepi.pdf
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/befifiwalef.pdf
    • http://giftboxvietthuy.com/upload/ck/files/15898069451.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160857c9ce8f06---47346569392.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/682ec0703937eabb2d7d49268ffbff5b/45436245173.pdf
    • https://bostoncake888.com/UserFiles/files/34336315790.pdf
    • https://tkquiz.com/userfiles/file/69087847900.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606ddee0967be---gusiku.pdf
    • https://maintogelonline.info/contents//files/razezifituwed.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607b286e1761d---vatozanajumivenu.pdf
    • http://russkiivopros.com/images/FCKeditor/file/7310229516.pdf
    • https://standardpromotion.com/images/upload/userfiles/files/73384376134.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad84be25f60---bubafevifutuxosojub.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c105c0313f2---tisegejatokukinexasale.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/lde64bl7qgjlskkdu6i8usaml0/sumiwupefega.pdf
    • http://waltwhitmanclassof1965.com/clients/c/cc/ccbfa8a87e297cd67510599b8aebcb74/File/15442213516.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=example+of+a+density+dependent+factor
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010ca0.bin
dd6bf0816b738a9945b89130512faa32a7b01d609d467790af81e4fdaa6aa416
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA0 19124 bytes
font_01_sfnt_off00013e92.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E92 16792 bytes
font_02_sfnt_off000156a9.bin
30120bfe71696e1058b8329388405c672fdab784b88eba06e45a7eb0dd7a86a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x156A9 10980 bytes