Malicious PDF — malware analysis report

Static analysis result for SHA-256 991f071bb11cc575…

MALICIOUS

PDF

77.8 KB Created: 2021-09-22 10:33:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c93335e8cc3029f4ca06d13d0eb8517b SHA-1: b31aa3f3669e0aa4d90cae8cfbbfd6a671f1d839 SHA-256: 991f071bb11cc5754549e4207d4298405f872537edd4532114e767d051c986c8
164 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript and numerous external links, many pointing to potentially compromised or disposable hosting. The heuristic 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest a malicious intent to redirect users to harmful content. The ML classifier and ClamAV detection further confirm its malicious nature, likely as a phishing or redirection lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 http://www.kotolantopeni.cz/files/3008290575.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/1etu06ogai5n3cc3ivaukkd8nb/dupikereb.pdf
    • http://wskinbody.com/data/boardData/files/vajirumupelaz.pdf
    • https://bamfieldrental.com/userfiles/file/82530311575.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/d25b178565ba0876936d2e4fde489178/29512358573.pdf
    • http://dmkert.hu/files/file/guwoki.pdf
    • http://we2meeting.com/ckfinder/userfiles/publics/files/sukajuvifuvufogoxe.pdf
    • http://caycanhtuyhien.com/uploads/image/files/lawibip.pdf
    • http://world-housing.jp/ckfinder/userfiles/files/45350143297.pdf
    • http://studiotecnicodama.it/userfiles/files/wakevujudapebeje.pdf
    • https://bestcoloringpages.com/userfiles/file/10533923538.pdf
    • http://canshu.dlzj.net/upload/files/20210921113818575704.pdf
    • http://akiyastyle.com/app/webroot/js/ckfinder/userfiles/files/78896620506.pdf
    • https://gifarlcm.com/upfiles/editor/files/80158531967.pdf
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/161370657d301d---tiwoxowepawo.pdf
    • https://helices-evra.com/userfiles/file/21542106688.pdf
    • http://hidrometa.com/images_upload/files/31083381282.pdf
    • http://www.shjkyq.com/up_files/FCK/file/vitigarurinepatevona.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db0272127b---piguxutewoduwotiwurarodo.pdf
    • http://sydjpg.com/images/upload/file/20210913_192137_147.pdf
    • https://sergeca.com.ve/ckfinder/userfiles/files/wapuzidibefajejedeziguf.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/981dc972ee4ae4b64f24704c057ee69c/depivegavunones.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+install+window+on+android+tablet
    • 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_off0000cbab.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBAB 16792 bytes
font_01_sfnt_off0000e3bd.bin
001cceeae043a021b35cca98521eca3c5d69610861241e4c4cc791df4a392b8d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BD 17876 bytes
font_02_sfnt_off000111cc.bin
f6b318b80936492d527ec3fcc2975afca1d4cb8f356b41b76fe50486315cd563
pdf-font-stream PDF embedded font (sfnt) at offset 0x111CC 10456 bytes