Malicious PDF — malware analysis report

Static analysis result for SHA-256 838f72a2fe36756f…

MALICIOUS

PDF

75.3 KB Created: 2021-07-04 00:43:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d548765199a6e0637d582b00952c83b4 SHA-1: 780bcd84ba9cbddf1f502ca1e9e0a9125688f940 SHA-256: 838f72a2fe36756f4efef6599bbee3cb17789218a4bb1b44a6115d858113058a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and other domains exhibiting characteristics of link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or distributing further malware. 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 container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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://hnsunnyfood.com/d/files/66551595467.pdf In PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/69339135285.pdfIn PDF document text
    • https://x-software.cz/data/file/57576989988.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/f77c376c1a6809de7ede55a5761eb084/bobizalimifixipadomogap.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/31abca8a0c76978ad41a9297093a5753/66717104385.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/0d5602347be5d5ca96bdfbf9b138bb45/musodirogopewoj.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e0f1c41f81---fijujoniguwujibe.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088793469ab2---buzipemitova.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/3692c3c19e91c292500fd31d0d37bb41/44151522427.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082475849a08---tamujijatugazuzalizami.pdfIn PDF document text
    • https://mimpi1pusat.com/contents//files/nuwomop.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/gf0rvk9u3u0uui3t6d427af8q7/rufojixofalapanove.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160c647c9ed7be---xitigetogiviriwuvurinojup.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9b5ab505a---92669767276.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/f9705a2fb6e9da1c22f2528ff4015a82/85549165944.pdfIn PDF document text
    • http://peneleos.pl/userfiles/file/91984135968.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/1abrbv84dbd138vip57ntmhjko/sumamozezuwikanixi.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985a65910ab---23243989800.pdfIn PDF document text
    • http://goergenpainting.com/clients/0/0d/0d1038892961fdbf96b6a8e7e8daca8f/File/vurokebupug.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a44bb76e92e---putogudaxevejakajofuxorif.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070936773201---53522232798.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/9qeu84m88j00vthajkm0660943/8398618438.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/4d2af66c196e9d03f2d69b7455f4578d/81057209810.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/62343526100.pdfIn PDF document text
    • https://cubic.is/userfiles/file/zelajuxusenedinunivo.pdfIn PDF document text
    • http://seabeachthailand.com/UserFiles/file/67473842104.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=english+worksheets+for+grade+1+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c492.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC492 15768 bytes
SHA-256: 4b29036c2a31252a06ddb46a80cf9ea8495733fe7f6414531a31e7fafe130ec5
font_01_sfnt_off0000ecac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECAC 10992 bytes
SHA-256: 6a4d807581499fa701d44fb10a4b7acb2ecf9c2d63c25d1d4c23110aecea18b8
font_02_sfnt_off00010609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10609 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.