Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5cdd40102675c09…

MALICIOUS

PDF

81.2 KB Created: 2021-09-08 05:57:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 71b208aace3487748759ca0fd9db56ab SHA-1: 0b1c8ed77e6fa0f0ac9092cb57e1a97f948ff645 SHA-256: b5cdd40102675c09fbdf37dcf3f85d14dcc3bd80817090ebc50bcb283ab6c407
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites. The primary purpose seems to be SEO manipulation or hosting potentially malicious content through these redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b57670eee24---72683078451.pdf In PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beccffa3976---nusefejupasoku.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/cc9df4829318a62fc55941375c0f770a/zokekovizutupudamobop.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/tenozaremowefajawukip.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/nisuxarewimilif.pdfIn PDF document text
    • http://melodylavernebettencourt.com/media/file/bewebono.pdfIn PDF document text
    • https://bangprice.com/bangprice.com/beta/cms_image/file/601697513.pdfIn PDF document text
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/d029c998ab47086d6f75f04069cf8c8e/36326396890.pdfIn PDF document text
    • https://ises.ca/phpsites/vertical_living/uploads/file/worozemararebilijif.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160719060b503e---85535993430.pdfIn PDF document text
    • http://origo.ws/userfiles/file/59389004070.pdfIn PDF document text
    • http://starlightcelebrates.ca/clients/4/43/43e9139217482d7666ce300faf566241/File/733315476.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/nadaxamuwitivep.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160a459ce186de---79824029328.pdfIn PDF document text
    • http://sdes.in/uploads/19335240272.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c5e76b3df49---sakaluwisukiwu.pdfIn PDF document text
    • http://dralituncer.net/userfiles/file/zerax.pdfIn PDF document text
    • http://awkontrakt.pl/ckfinder/userfiles/files/rinadubumesafogesubis.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e2b372a9e58---18694120342.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/ligelafefogifaleja.pdfIn PDF document text
    • http://yasairamenbar.com/uploads/files/lopetediluto.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/kinetabuximaweve.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/0f89add9f3b03c900261111b3053c2e1/13573517794.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/ss9fbvnri2q46isr9ro3vf81k6/vokiremomenug.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160a29f57456b6---zuzosodutinem.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/jaxeg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=pdf+to+word+editable+converter+online+free+without+emailPDF 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_off0000d6df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DF 17888 bytes
SHA-256: 0fab44f74da9be8f75916841841f434b33a5bd491f7428d2e006381f95613a9d
font_01_sfnt_off00010522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10522 10968 bytes
SHA-256: f896539e5d20bf991b8e40ef980014e7b714737643ffc1a3844e471f0dca6d4f
font_02_sfnt_off00011e69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1