Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae82cf0bc541554e…

MALICIOUS

PDF

84.6 KB Created: 2021-10-09 10:30:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c5cc40273bd6082e9ddb8533cd4cc10 SHA-1: 803f264a30cb0e714703ff570722a3c2e4afb0a9 SHA-256: ae82cf0bc541554e132c440a63d2bffa77578593aaa5941af6fc0a60279f3adf
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF containing embedded JavaScript and a significant number of external URLs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these links. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://drafthe.ru/uplcv?utm_term=monkey+trouble+class+7+questions+and+answers
    • https://s-oil.hoakhanh.vn/uploads/image/files/zuluretivanir.pdf
    • http://pytextiles.com/userfiles/file/rajakagakip.pdf
    • https://castilloexterior.es/ckfinder/userfiles/files/tarurukifeda.pdf
    • https://dgssu.com/upfolder/e/files/20210905140717.pdf
    • http://marta-galan.com/files/varios/file/puzegowiradikanilez.pdf
    • https://mmagame.com/userfiles/file/30068325632.pdf
    • https://alicantea.centralcms.cloud/galeria/files/gopubipiru.pdf
    • http://beccaro.it/userfiles/files/pefefuborepuwidetar.pdf
    • http://www.sudaff.com/pics/file/77930901909.pdf
    • http://gazduire-domeniu.com/UserFiles/file/32337539582.pdf
    • http://ghinelliarchitettura.it/userfiles/files/vitagufotage.pdf
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/dawefosoguxep.pdf
    • http://aburobocon2019.mnb.mn/uploads/files/ritakazomufopavulabixedub.pdf
    • http://www.bordadoindustrial.com/ckfinder/userfiles/files/62889854952.pdf
    • http://minhquoc.vn/uploads/userfiles/file/subexowunajukubu.pdf
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1615c5e9055847---tibibopilawitux.pdf
    • http://esangsok.com/upfile/files/45635790822.pdf
    • http://kangshi-you.com/uploads/files/202109101548097005.pdf
    • http://www.musicboxpiano.com/contentfiles/97660160323.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/9dbf1c2ed5a7dbbe53a03aeee115b263/71158455535.pdf
    • http://yakutiaprime.ru/SITE/files/editor/file/liguwifurekunar.pdf
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/fa3aeb9623f8a56e723d2c67b08f9fa2/98953488278.pdf
    • http://amandatour.ru/js/ckfinder/userfiles/files/dutufeso.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1615fcc9d76f53---76957395933.pdf
    • 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_off0000e382.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE382 16792 bytes
font_01_sfnt_off0000fb94.bin
23a078f137b5e94e65e5fd05d98df754cec1c5ee3bd19df332662d8aa9cc91e4
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB94 18152 bytes
font_02_sfnt_off00012ad0.bin
7592c6dac7f0a8a41d0554ffce264f1f83d61cb06284267242d1e28663395079
pdf-font-stream PDF embedded font (sfnt) at offset 0x12AD0 11084 bytes