Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b21b3b94635be8d…

MALICIOUS

PDF

72.7 KB Created: 2021-07-09 20:16:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 49ed8c9bd738da552d95495778a92dba SHA-1: 5e8cbf362a8c987b70bd959e2cf9faae8f76ef2d SHA-256: 9b21b3b94635be8d0328a5532d3d6af08cdea44b1303465ba67bba137bb94018
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and UTM parameters points towards a coordinated effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://smidgel.ru/uplcv?utm_term=national+professional+soccer+league
    • https://aonetreks.com/uploads/file/lizokofuzugijewu.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609840672aa6e---wesiwi.pdf
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/fc93b8a74d5347c08ec688eafef87946/mexazeguz.pdf
    • http://yachtandgulet.com/userfiles/file/73340819132.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/098d4128a368da6262dc3de921cafe31/1761298840.pdf
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/60688d7fca6a1bccf7fc4c23ecc4a47f/xobamo.pdf
    • http://driver-jazda.pl/upload/file/wixalujoveporinubeseraxa.pdf
    • http://stpetersame.com/clients/9/91/91902b33218228c9a3691be2563b71f1/File/bafolenukoganiv.pdf
    • https://inijariku.com/ckfinder/userfiles/files/67964222614.pdf
    • https://emmaushuis.org/pages/luzuxexosupusojezako.pdf
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/c83806c23de9e3528f9d76648b23c042/29257387669.pdf
    • http://murasakijr.com/uploads/files/53941631827.pdf
    • http://tzoetemondje.be/uploads/files/panumevixem.pdf
    • https://infiniteprospects.com/FCKeditor/file/xurolixov.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f1b03d4f5---95788745937.pdf
    • http://www.aqsclimited.com/EditorImages/file/19442518860.pdf
    • http://classicalgardenornaments.com/uplds/file/27077690690.pdf
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/0c0aa6ee40b91a0f24023b236ccac852/keripopu.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160703f9422ae6---livurufomefow.pdf
    • https://pearproperties.in/userfiles/file/wotejebezinotuposemofo.pdf
    • https://getracemirates.com/userfiles/files/71617972540.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b833552c3---68188968164.pdf
    • http://emailreceptionist.net/userfiles/file/53235445776.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/f8806b37757b87394afbd305fd1c1e36/divumimuxivowitar.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/6dfbfd5cc04f4af134f480dadac91ccb/sejesokazeduvir.pdf
    • https://narimasu-chintai.net/jcfiles/file/55315167008.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160c6d23aa3bb8---zedovixijipajezemut.pdf
    • 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_off0000bc3f.bin
491f3a87414184b83256f48f09e69f4ea05b57a81e80abfcc963bacf00c340cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC3F 10732 bytes
font_01_sfnt_off0000d50f.bin
eaff9b2342ad26da301e81d4caaf4b3256796a63fdcca3b8c1ff4a2a6fe85af4
pdf-font-stream PDF embedded font (sfnt) at offset 0xD50F 15792 bytes
font_02_sfnt_off0000fd31.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD31 16792 bytes