Malicious PDF — malware analysis report

Static analysis result for SHA-256 5cfe94a1c317038b…

MALICIOUS

PDF

76.3 KB Created: 2021-08-28 02:53:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6a29a0a57dbf0ef1f3cf8819c3615712 SHA-1: 5ffdea6a3253616eb1abcb3564c3bcce3a14c3ba SHA-256: 5cfe94a1c317038b3a6d25e8bda716af50bdabb86ee1e448349cea6d654a3178
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to compromised WordPress upload directories, suggesting an attempt to host or distribute malicious files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • 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://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16126a7a7b9a67---voraxisufelavapememutifaz.pdf
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/fb4ca210908aa3b2d45b418dee62069a/kejawotakob.pdf
    • http://orlickachata.cz/files/files/57534875946.pdf
    • http://bajcsidavidfoto.com/_user/file/80221670977.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16117ad26f0e0d---lifodanaxinajafigavu.pdf
    • http://alternatifmedikal.com/img/userfiles/files/82375785870.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160762f88d150d---rofilufofubowolasix.pdf
    • https://oreopay58.com/ckfinder/userfiles/files/xaxedurerikur.pdf
    • http://bycongroup.com/UserFiles/file/fuzodurodologixiti.pdf
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/83487094020.pdf
    • http://bestbelly.org/content/files/files/59796705679.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/2303aafb7b72a9b4b50dfc7bcf8fcb65/kenosobex.pdf
    • http://ex2010.com/uploadfile/file/2021081821181173499.pdf
    • https://dptech.vn/uploads/files/92835492788.pdf
    • https://prestinieurope.com/userfiles/files/tivovakewefiso.pdf
    • http://bcslaw.hu/admin/fck_upload/file/takixoregupusuvosefano.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b64a2c964ca---jidid.pdf
    • http://kiuanai.com/userfiles/file/65837946895.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/ba3ef1e6720b5af438465f57de57bbd9/baxerifenedodadofixi.pdf
    • https://k-barrierfree.com/FileData/ckfinder/files/20210703_6D3C23795034ACEC.pdf
    • http://noahjohnsonsark.com/clients/e/ef/ef24418f2336b9480f3353ee42fa3f58/File/xukixemawumug.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/5f7250eb10869b6116780ba447434b2d/sojutawumevajawujak.pdf
    • http://ytovietnam.net/ckfinder/userfiles/files/rikagovami.pdf
    • http://epoch-making.jp/js/upload/files/kakizepagube.pdf
    • http://interfacetravels.com/app/webroot/js/ckfinder/userfiles/files/33924112886.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+delete+watermark+in+word
    • 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_off0000c8f0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F0 16792 bytes
font_01_sfnt_off0000e107.bin
d042594c0a306e2d59baf08535b0d4f7cc6174334ec30aab0161019e5c0869b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE107 10408 bytes
font_02_sfnt_off0000f885.bin
d108275f6d711788ccae22c92f493fac80241696cad84afbd2b2c1ea7f0e138c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF885 16612 bytes