Malicious PDF — malware analysis report

Static analysis result for SHA-256 624a3f5a6101c628…

MALICIOUS

PDF

91.1 KB Created: 2021-07-17 17:11:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 92375a605e8241b75b8f29600d428450 SHA-1: 5cddf2c2f71962a01ca9b910b8a1529c5c5aa51a SHA-256: 624a3f5a6101c62879388c96af26f44fcff05dd20db9d711047f7eb1c9f23a6a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised WordPress sites acting as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript could be used to further obfuscate the redirection or initiate a download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 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.
  • 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://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/46f93f839de8d982ef4765b1679aa0fd/vufawapodudukebul.pdf
    • https://unicorn.mn/js/ckfinder/userfiles/files/nekuruwubuxa.pdf
    • http://entryexpress.online/chapter_images/files/58512804202.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/bc16b91f98a1a7587469c258cd87e89d/20981740044.pdf
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160cbd3a7508ea---fegawututasedalumaxarat.pdf
    • http://ahcxdq.com/uploads/file/04080050689.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1608e40748fa09---2932158194.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948a3fc7c15---pawovadirenusolu.pdf
    • https://krassimirtaskov.com/userfiles/files/6023326925.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/s0ede29t9c2m3pmfn5tsmp5ng2/74395780165.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/e2d7a3f4236ec8067c506bcc0e1de2b4/bigidukajixujowumomuxud.pdf
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/gubomupo.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608041ac75ee5---87182904631.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097ec9376214---66408005446.pdf
    • http://palirna-frydek.cz/uploaded/file/65418654749.pdf
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/xivefizefomisevad.pdf
    • http://duda-tech.pl/dudatech/upload/file/rigomikogakibifesu.pdf
    • http://rideabikenews.com/user_img/files/35679129737.pdf
    • http://anaminfo.com/attachfile/file/pofige.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c31b8a79438---fugudalibosakuregub.pdf
    • https://tideandtigers.com/ckfinder/userfiles/files/segezigefa.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/eb2833ec15164a6adf0773ef71174b84/71186395837.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/hj3ab6huv1sppkbd9cjnbggf82/84785390312.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=72.3+kg+to+pounds
    • 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_off0001026d.bin
587bac2402c1890e6b96d1a50aa0381272cfbd99e86b16ed971dd985f8de8e5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1026D 10536 bytes
font_01_sfnt_off00011a7a.bin
c543674ac1aec74503e710f2a45208a0a274f1fd65a1d76c9e50d30ce94b51bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A7A 17400 bytes
font_02_sfnt_off00014798.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14798 16792 bytes