Malicious PDF — malware analysis report

Static analysis result for SHA-256 31f983747be50234…

MALICIOUS

PDF

85.0 KB Created: 2021-06-27 22:17:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 20752575210cbd0882b1faa7a94da6ff SHA-1: b4efa7485a0830e69d83a9e763e2461529b505f1 SHA-256: 31f983747be5023427b70b226b3c855f10a4e777aa455823e2bbd90353e13783
172 Risk Score

Malware Insights

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

This PDF sample was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and numerous links to compromised WordPress upload storage and disposable hosting suggests an attempt to host and distribute further malicious content. The 'SE_DOWNLOAD_BUTTON' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210512015513854917eiws7w.pdf
    • http://denki-shonan.com/uploadsfile/mamixedonejerusurivo.pdf
    • https://psfund.org/public/uploads/files/cms_files/42378833601.pdf
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606fdbf8092b5---dikuziziworid.pdf
    • http://dissanna.com/temp/fckeditor/file/jumojijumuxase.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6c2f93aede---joxomefowomikekixo.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160a05c7160c22---78845228770.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a475a431dce---potawatupebisojiwatis.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae34b22ce3f---5163877674.pdf
    • http://homeopathyhongkong.org/files/webirixuzadogadumasijo.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/8798faaffcb42d8208bd82c7ba7f246a/bokekudirevokitura.pdf
    • http://taskentcompany.com/userfiles/file/sirutajazapawosimole.pdf
    • http://hillcresthigh1971.com/clients/9/9f/9fbf9047a6869172a982db6f42f05a9a/File/libuvipupipenovakisax.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/cab364a8f67f07bacdee08bcd23e0689/74250660548.pdf
    • http://indago-rovigo.it/userfiles/files/makatoleriratekilemagebi.pdf
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607217d25bf04---58950924119.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160888698d6efa---3356174339.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608288f6e8c2d---36207505897.pdf
    • https://sasalidayanisma.org/uploads/file/18182401761.pdf
    • http://prime-standard.com/piceditor/file/29952239445.pdf
    • http://gymostrov.org/gymostrov/userfiles/file/26096763396.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa37af81db0---21496791057.pdf
    • http://divorcefinance.nl/uploads//file/19266453048.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa5e9f2bde---77614978016.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=got+a+whale+of+a+tale
    • 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_off0000ec15.bin
f352cb8ccaddff07fc44c2245f9931f7155de3784effca55c2ea1f9c01877dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC15 17120 bytes
font_01_sfnt_off00011875.bin
bcf4430aafc242c84dce59642cc5dfcc2906e51417f3246ac7b60fa7b5a595ba
pdf-font-stream PDF embedded font (sfnt) at offset 0x11875 9972 bytes
font_02_sfnt_off00012ed2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12ED2 16792 bytes