Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4f9dafee62f8f7c…

MALICIOUS

PDF

66.8 KB Created: 2021-10-08 06:18:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8c66cb5638498509d5576cd9f8ebbd2d SHA-1: 7fd6423f7f29f19faedef57aa525ca556872995b SHA-256: f4f9dafee62f8f7c7735f3023c0d1a5bdc3d746df0a695101ee641324339f39e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, with many pointing to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6095

Heuristics 5

  • 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
  • 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://catamma.ru/uplcv?utm_term=rrb+exam+model+paper+in+english PDF link annotation
    • http://russia-ex.com/images/blog/file/fonukujatekafetav.pdfIn PDF document text
    • http://romanasulcikova.cz/userfiles/49340772993.pdfIn PDF document text
    • https://bepcongnghiepphuchung.vn/userfiles/file/50254933999.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/8cb6dd9b0fee793e1f904c4274945a0a/24521154107.pdfIn PDF document text
    • https://hkki.org/userfiles/files/54734749548.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/widuvilokurev.pdfIn PDF document text
    • http://jianianhuayule.a9188.com/upload_files/art_files/files/20210910_221105.pdfIn PDF document text
    • http://maytinhnangdong.com/files/uploads/editor/files/92618380637.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/ziluzisixobafebob.pdfIn PDF document text
    • http://kaitianjinghua.cn/admin/userfiles/file/202109191104269863.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161478511142bc---salojotarinubelobe.pdfIn PDF document text
    • http://dietetyka-24.pl/images/files/tibuzezitadanegaf.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/02bc1bdc8cff9478a7ffcde3650bbd8b/fekesiteg.pdfIn PDF document text
    • http://sirindhorn.net/upload/File/3217340235.pdfIn PDF document text
    • https://alshuka.ps/ckfinder/userfiles/files/razevubifodozowosobim.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/lulirilurasi.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/13549071190.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/7775654c1091688cc08986669dcf309e/21744529671.pdfIn PDF document text
    • http://cke.hk/userfiles/pikesipurevafinomotu.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/jasasujipa.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1613f80c017b37---kijanumudunu.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/49976190627.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/buxotojixoxujuzesu.pdfIn PDF document text
    • https://empresa-venta.hr/files/jowuve.pdfIn 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_off0000b378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB378 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB8A 16616 bytes
SHA-256: df164fd7a5b56aa82fabf13b09e20294405f59310fccdef205b003043df52f43
font_02_sfnt_off0000f68a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68A 11028 bytes
SHA-256: 890d16cd84b242b85dcd902cfa14e9385fa4778acbb0cf476f0e40f96901eff8