Malicious PDF — malware analysis report

Static analysis result for SHA-256 5652b9b581a7aba1…

MALICIOUS

PDF

85.7 KB Created: 2021-07-03 05:47:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 76fc6216a03a1db265b692352e49ad97 SHA-1: b282143c6bb2f105e362704ab573a23988cefff7 SHA-256: 5652b9b581a7aba10331f0d21a3263fbb66ba76660081c7712ae3eb00c34a483
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://berallebags.com/UploadFiles/FCKeditor/20210626112559.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c3ef0f92b---68986631805.pdf
    • http://amdind.com/userfiles/file/4046030779.pdf
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/rohiqt4hmbe72e9t0l358c6c57/daxikukasubawumi.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/krf7fsdupo7tlmqljcousin1t3/48027449046.pdf
    • https://gregor-biffiger.ch/userfiles/file/vukuda.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/f9b6e867775662da11946dc8cf77ce8c/95038810846.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1609865ff52bf6---wudakomukitelu.pdf
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/6fe645a7b66a6b2dc8a9ce2fe66878ab/5586045516.pdf
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/n1hfkt3ni2uvddnpjid5kjvqgm/68325005747.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4c20cf878---22199314608.pdf
    • http://asea-admin.com/_userfiles/file/20210702135542.pdf
    • http://fairway.cc/images/blog//file/86493793553.pdf
    • https://accuratesearch.com/userfiles/file/xowog.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/c3cf02c89907445c031ca4301b6d62b1/dosodonekevunoloxutod.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a401d4821cb---rinavuvaduwososuduzuf.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/7895cd543fbab47dacb357034ca55424/vubepobafamibiwero.pdf
    • https://acgroupenterprise.com/userfiles/file/zizexivemumunipozareba.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160d6887d5fc7e---pusopilubo.pdf
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/9f9f7680a962cc1b99360184647ba03b/fativedobopoxorevavulofe.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4e270224f---75283848757.pdf
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/qg1uk9c7l32pgjqbq81nc6btgt/denimunolarukowevivogeten.pdf
    • http://investin-khj.ir/ckfinder/userfiles/files/nonemebepudigijoxeluv.pdf
    • https://reinigungsfee007.de/wp-content/plugins/super-forms/uploads/php/files/1rg2ut8qk6eellv8ovfif4v0ib/zijudem.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=nail+color+and+health
    • 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_off0000ed36.bin
4cc0bd22021766e7f00671aeee0be670efd4e90cbf557493cf703e03349dc625
pdf-font-stream PDF embedded font (sfnt) at offset 0xED36 17716 bytes
font_01_sfnt_off00011a8e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A8E 16792 bytes
font_02_sfnt_off000132a5.bin
cdfefed717d98c6fe5ee0bb70db9ecfb92ce8ad95be1d538df23c289e103d983
pdf-font-stream PDF embedded font (sfnt) at offset 0x132A5 10276 bytes