Malicious PDF — malware analysis report

Static analysis result for SHA-256 c41b76aa07ddc06e…

MALICIOUS

PDF

76.4 KB Created: 2021-09-07 08:18:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: be9ee46b0d8dfaf716026ba0357b6a4e SHA-1: 0c25ad8e33729cf12652ee884849d49617b663d6 SHA-256: c41b76aa07ddc06e9a17654b25f49fd0f8e64e23a8c5ec85bb11cf8d72d78cf3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed for phishing or malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent. Although no scripts were explicitly extracted, the presence of external links and the nature of the heuristics point towards a malicious document likely intended to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://synerhu.ru/uplcv?utm_term=printable+secret+santa+wish+lists+pdf PDF link annotation
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa5f7859c0---84413493933.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/pnk7br5sjgogh5nh889bcsfia5/mavimo.pdfIn PDF document text
    • http://africareview.in/userfiles/file/xugisitonodewotevezumu.pdfIn PDF document text
    • http://orsolyajuhasz.com/ckfinder/userfiles/files/zumavopu.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609869b36a632---58769126665.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///20210815175336_1015921608.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/fd8e226e22884377854bc93ca7381e54/mirijoxizirudipajefe.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612cadced9168---48247702451.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/42908708811.pdfIn PDF document text
    • http://klhl.com/userfiles/file/22051599718.pdfIn PDF document text
    • http://mwcapital.net//ckfinder/userfiles/files/fatojutadekuwasu.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/mewizelomuzewojosimozif.pdfIn PDF document text
    • http://xn--80aab8aioy.xn--p1ai/userfiles/file/pobolimagazemumodur.pdfIn PDF document text
    • http://rafaelstore.ru/upload/files/75757119394.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/k3p6vnmrisn72b5040sio5pk81/22275385638.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/tuzisefo.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/xolalagigufefezakogogidej.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608845d321d46---lixopizodiwewavovaw.pdfIn PDF document text
    • https://spacio.hk/attachment/file/54349547955.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/14036s9cpil6fo26pli15ao146/riputakeviludujusoki.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/pavovarorubo.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/3536533668.pdfIn PDF document text
    • https://pristineleather.com/userfiles/file/wijigazure.pdfIn PDF document text
    • http://ulv-fogger.es/d/files/rawojetagulesob.pdfIn PDF document text
    • http://pereplanirovkaoblast.ru/pict/file/vamubiv.pdfIn PDF document text
    • http://jentretiens.ch/uploadimage/dinukoxo.pdfIn PDF document text
    • 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_off0000c89b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC89B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e0b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B2 10824 bytes
SHA-256: d697bdf3cfc93d92c12ef0a367369ce0534aa976e9204d39bac5afccf05be1aa
font_02_sfnt_off0000f96c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF96C 16400 bytes
SHA-256: f3801faa4f86c1340def38acccbef216256209b4cf88f5f3174aff5c8b194c83