Malicious PDF — malware analysis report

Static analysis result for SHA-256 1adc3c15b31bdd42…

MALICIOUS

PDF

85.4 KB Created: 2021-07-17 22:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 881205d0bec1ca9db5794897ce0f0ad0 SHA-1: 00d5b2b858c18db22647c7daff9a4a58b82cfb50 SHA-256: 1adc3c15b31bdd42ce643bc1c707d4c092406d9986524d3d863f94710fbc2695
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting it functions as a link farm to distribute further malicious content or phish users. The presence of external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://www.advokat.com/app/webroot/img/fck/file/79049277336.pdf In PDF document text
    • http://www.kickcommerce.com/userfiles/file/56156420652.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160780d06de2ca---pebanoxoxa.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16093ea03d4bbc---48854412220.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/54a0639f18b5c86791f9dbc478f2a56a/2825430696.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a41c6f011ba---buvopusov.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/4c00498a4f64add8f8313a7f51531895/kamob.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/916458337.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4b53d734a9---51763031624.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/95076573750.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/migibokelob.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc28466e68---56373476527.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073b0f85eb9f---zefufonisixijapalos.pdfIn PDF document text
    • http://podlahypilat.cz/admin/file/lewopefoz.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/22dfea9777467034f12cb48befc0b5bd/ziwokokamitibadufuku.pdfIn PDF document text
    • http://tebsc.com/clients/84181/File/30882233978.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f0691ceb4---50630568944.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbc28d209b---negizemolubened.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///67101777823.pdfIn PDF document text
    • http://waypl.pl/upload/File/gufudekelafesofi.pdfIn PDF document text
    • http://eszixv.hu/ckfinder/userfiles/files/791227534.pdfIn PDF document text
    • http://skupka54.ru/upload/m/82728221064.pdfIn PDF document text
    • https://kalyna.ua/sites/default/files/userfiles/file/96147744059.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab30fc526a---gagefoj.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/kewagawatufuti.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/62874375460.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+combine+files+into+one+pdf+on+iphonePDF 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_off0000e774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE774 17528 bytes
SHA-256: 99986bdba6c52d029a69c3c0fe9fe1e60186572e3b8061672513d1f8b888d7d4
font_01_sfnt_off00011532.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11532 10840 bytes
SHA-256: 9ef7f0126e1a7d17b84b35f1d993ca3c62e7d9eaa472c38c0ac216c26bcb1c55
font_02_sfnt_off00012dc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1