Malicious PDF — malware analysis report

Static analysis result for SHA-256 c41d75cc58ce553e…

MALICIOUS

PDF

103.1 KB Created: 2021-06-29 01:22:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9ba700e582b1957114dd5cb00f6cb662 SHA-1: 65aeaed5435281587ab5654b756e13cdc813e011 SHA-256: c41d75cc58ce553e368dfd2ba16f55889403508d3cdb84af101e17cfd472e634
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing. The document body is heavily obfuscated, but the heuristics reveal a link farm strategy, likely intended to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

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://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/0b757228a7e7f3b19d54519b91333803/kezimuxikamogipu.pdf
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/3749c2529d46b356eddcbfeb42e776c4/supemifufi.pdf
    • https://akproauto.com/nbloom/fckuploads/file/kafujikonolasegamiji.pdf
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/33b3081c8d4a063db11b9463a882b89d/55690966597.pdf
    • http://cl-pub.com/files/files/kowudukixat.pdf
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/to1l5ppqfh3jlhpio3ad3okqm2/35496716298.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/0f11570d0626c2e0091e867771abe961/52791839433.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9d33c2cc9---muzojuzotumi.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4be902af4---wulosefibozowajizukiligif.pdf
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/gugomireverabobojito.pdf
    • http://fsoa.cn/userfiles/file/suxodidesanodesexuvagif.pdf
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b8fdf94f5b3---vidolufik.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160995fc10dfd0---18426231079.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c888c20507d---simuf.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff231a1097---91185127384.pdf
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/jajagek.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160cdbf12a91fd---89262874819.pdf
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/fd3a797d76d48c53a715339b4cb58eb6/paliwesewawelumi.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fac1c0665---1286992839.pdf
    • https://areicon.com/images/file/72128553777.pdf
    • https://mayurherbal.com/userfiles/file/jilimurasisiz.pdf
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/fvhim79lm1g9l3st7svtc1vq1k/sekapig.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/dhjjuqb2qha62ieumuucdv6ua8/31797703106.pdf
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/11490169746.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=define+the+availability+heuristic
    • 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_off000131f2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x131F2 16792 bytes
font_01_sfnt_off00014a09.bin
df28ac6e10e643f643e20678acf4cb9613aae1669d44c9dde6fefd0461f5ef9e
pdf-font-stream PDF embedded font (sfnt) at offset 0x14A09 10736 bytes
font_02_sfnt_off000162af.bin
dcbaa32fea3eafed6cb112ede651cf82223204d31edac6f92a560c4c1dfa3778
pdf-font-stream PDF embedded font (sfnt) at offset 0x162AF 17320 bytes