Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c76cc90e755a384…

MALICIOUS

PDF

81.9 KB Created: 2021-09-05 20:17:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 37381bdbba37eecc715664b678b0d12d SHA-1: b4e0c00e92c2642d3bf595e8d56d9ed3bcb4e1bd SHA-256: 9c76cc90e755a384c9aa95f59c5701c5ca8ae6cab764e6c16239920a3e96549f
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external sites, many of which point to compromised WordPress installations. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass gateway security. While no scripts were directly extracted, the ML classifier and ClamAV detection strongly suggest malicious intent, likely involving the download and execution of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d55affe7d9a---98234325699.pdf In PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/dcbaf56dda8c67a583af448355aca7a4/53406864002.pdfIn PDF document text
    • http://kaies.net/upfiles/210801072744308099fl1yer.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/cf4b0024b63b6e40c555ada163f25036/681730229.pdfIn PDF document text
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/6781682088fvqqefs0t4l407ss/nutowerevuz.pdfIn PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/fagoguvipawapaganufali.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/d1583ffcaa2bbf1f06bbb9a1b81439e7/pemapatelisukegemigoroja.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/47478451913.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/62321550508.pdfIn PDF document text
    • http://miraesusan.com/ckupload/files/wozelilitapomitonuj.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/ketez.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608885944c166---23566257155.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/6d3fb764e56124338fb4b73ad3798ef4/21078845834.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160c26b5d05e14---sasuvaxewenapu.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/watidozokosokikizaloxebab.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607658bb5bfd0---wimiwoza.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/61005731155.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/pp37cv13e0tbh64cif99c8q1c5/marewasakanudan.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160ba3f22a4c43---46422260740.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/12872514278.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/b4395aabce77ba6388e4a533e84af238/20562371992.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/wudedagakuliboduketegigal.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/95983338735.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160edf284a000c---45273583378.pdfIn PDF document text
    • http://drthchowdary.net/userfiles/file/wukefuliwag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=logiciel+gratuit+pour+combiner+pdfPDF link annotation
    • 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_off0000d876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD876 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f08d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08D 10992 bytes
SHA-256: e3abed585271e6e47191e8c477b832b7b22ac4787aebd18a66628d98e2e9e54a
font_02_sfnt_off00010999.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10999 18836 bytes
SHA-256: 1ce540339e92611a4da32059073ea52d9aa98796ed2c6d2c32986e9619c42d38