Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5799342ec1978b2…

MALICIOUS

PDF

82.2 KB Created: 2021-08-31 23:21:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5213b8f5652fad4e159bad8779382988 SHA-1: 58e64c955bb60ddf028cf6bde4f01506998e9d34 SHA-256: b5799342ec1978b238788f0a0c0dd6db5d372ce1d34f64f39f794b62df9c6ced
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It functions as a link farm, directing users to numerous external URLs, some of which are hosted on compromised WordPress sites. The presence of 'demodex' in one of the URLs suggests a potential connection to known malware families, though a definitive family attribution cannot be made.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://cyc.cz/pictures/clanky/files/busawilivarubizikirip.pdf
    • http://phunggia.biz/userfiles/file/bokejogilojariroratudeb.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/b0185b17942d886dc87f790f8bb27cd2/fadaka.pdf
    • https://caribemed.com/userfiles/file/65769884732.pdf
    • http://fabriziocar.it/userfiles/files/55134455394.pdf
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/5f32bd9972014f4331ea46cdc18d0503/serupuzugevunizowoxatevev.pdf
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/bbd8524361d0049e396b254a0311865d/30809464839.pdf
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/98r7l9akaal01dtr6rfk0a59n6/zisidosur.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c47d7ead4---dazigenulepovo.pdf
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/8f03675b8dab7349dbb99598dcd35b04/wigovamobarado.pdf
    • https://beautyyaurient.com/editor_upload/file/88857648523.pdf
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/876f6b942f74ba77db5ae1daa5fb54d4/13506503810.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607167efc6f70---gudujatonujus.pdf
    • http://esllearningbydesign.com/app/webroot/files/file/mejurumugep.pdf
    • https://kawanmto.info/contents/files/93695874504.pdf
    • http://bostonmentors.com/userfiles/file/wepisaximozev.pdf
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088e9a94912e---40220665698.pdf
    • http://mpu-beratung-brendle.de/userfiles/file/48764022181.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16074022956baa---74781857971.pdf
    • https://medprobr.com.br/wp-content/plugins/super-forms/uploads/php/files/0399c428deef91978b06912e8645e6fb/11402745228.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bace50e687c---tiwibilaxad.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/53bca631924f7ef16c09a0c2c7f2fafd/wolamupufufanurorumosa.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d5bcb334f---jubanaduvalafofe.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=demodex+in+human+face
    • 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_off0000dfad.bin
81071d429cff40fd83659b34e4100e2b14d72cc960816317b94abc434cdd3578
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFAD 10532 bytes
font_01_sfnt_off0000f76f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF76F 16792 bytes
font_02_sfnt_off00010f81.bin
e4bcf474b6cbec513034ebebe69b6a551d27791501ce212fdddec97ee00eb813
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F81 16748 bytes