Malicious PDF — malware analysis report

Static analysis result for SHA-256 82edbf958280aa3c…

MALICIOUS

PDF

79.4 KB Created: 2021-09-05 06:48:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: db3086502dcd8d24b5cb9923aa8ba102 SHA-1: 181aee4d80c38a48a0d9d96aa7000ad02e4a6407 SHA-256: 82edbf958280aa3ca60f6b87b06b10eea2523597834ea314279c4b991b5095c5
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple URLs, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body was unreadable, but the heuristic firings and numerous extracted URLs point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://nsck-cykelmotion.dk/userfiles/file/32019263166.pdf In PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/cfc61698c99649d384cd239bb8ef3223/wuvesowijimoz.pdfIn PDF document text
    • https://monamifrance.com/FileData/ckfinder/files/20210815_0E01438D5C37E03F.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/75819080460.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160fc86a56ed8e---nuvikojijib.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/9a6ffea1da745d0f5502557b605d23f1/vafuxogifupisizoma.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16118689cefe53---radezolewajazuzuw.pdfIn PDF document text
    • http://parquet-cortes.fr/data/Files/ganiperosawideteximosanez.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9e7ada750---39018837205.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16090962c14d34---75274062755.pdfIn PDF document text
    • http://abnicum.ru/files/file/fijulugoju.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16072519069beb---lejiva.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/7e817a9a625b31686a56e5a669460d1c/4093967629.pdfIn PDF document text
    • https://triosms.com/userfiles/file/77566626466.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085af798c538---latolazokolopef.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/73308174067.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/n01tccmlfq3eqfoj9djcu67329/82122930036.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1626694075.pdfIn PDF document text
    • http://gmei.lt/ckfinder/userfiles/files/sajefuxagemovo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=google+doc+pdf+to+excelPDF 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_off0000d3a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A1 10308 bytes
SHA-256: 2e20cfe492a76800cfba926513be838fd31267323b3b658faae25eef5023542c
font_01_sfnt_off0000ead0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD0 17620 bytes
SHA-256: 10179e2d9a47d16ceec8c2a59f44d7c8a8bc83b3749a875fd5f08b13ca874db8
font_02_sfnt_off0001187e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1187E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1