Malicious PDF — malware analysis report

Static analysis result for SHA-256 b45171a5c5c31583…

MALICIOUS

PDF

74.8 KB Created: 2021-08-10 10:13:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aa773075a6c302a05eda69551d90c822 SHA-1: f41d17a552f7bdfac623223b24cd5aec3c54598a SHA-256: b45171a5c5c3158362a1a4a0157629a9d299c164bd5c02d10058888f9105cfea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many hosted on compromised WordPress sites, suggesting a link farm or redirection mechanism. The PDF structure and embedded URLs point towards a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://queure.ru/uplcv?utm_term=ncc+army+handbook+pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/f092282155c6cee8e722bd717bf008c7/91594943551.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff14210643---71697593695.pdf
    • http://centralcogtc.com/uploads/file/35768447235.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc35af018b---51206765373.pdf
    • http://alternatifmedikal.com/img/userfiles/files/wewebaxoteliwuzinefuwa.pdf
    • http://calliopegoodrich.com/clients/73417/File/lebidovit.pdf
    • http://klimagra.pl/images/wysiwyg_img/file/gewujetumojabej.pdf
    • http://georgekoldun.com/var/upload/file/49548867669.pdf
    • http://shsuorui.com/uploadfiles/fckeditor/20210626/file/16247084084619.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608549657501d---gavewekotudu.pdf
    • http://yhbinternational.com/userfiles/file/gupumozulajis.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b58ed55e367---96532945386.pdf
    • http://soupworld.de/upload/file/61819597880.pdf
    • https://brahmagnanam.org/fck_uploads/file/59415393976.pdf
    • http://lyonsmcafeereunion.com/clients/a/ab/ab8eb7fa8d7cf94b91f67e7e346c80ed/File/64038009182.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6f74a1a59d---vegutusewixateroni.pdf
    • https://gamepinleri.com/calisma2/files/uploads/gifixesatev.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4caf7e0ffb---luzuxewozozudatulit.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/f9301f4a901e79e0b4f6c8605f9f7655/59042141337.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/ada0c4a66aa7cfc3315562220c3b4ddf/nugokamizatorujopa.pdf
    • http://inphuduong.vn/upload/files/vumutovomaxame.pdf
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/b8e23ad1f818867127146f1504199a34/garoxozog.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aca28a93a5d---93963515045.pdf
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac7cdd3ba5---neturebin.pdf
    • 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_off0000c0e5.bin
96433f44c76f62d75869662ce57835543b7df3adcb7b40c03c05277b0d67ac66
pdf-font-stream PDF embedded font (sfnt) at offset 0xC0E5 16740 bytes
font_01_sfnt_off0000ec7a.bin
70f8c26907049501bedb2a996ce18c07f5e51c0963d4a047cfec7ff1aff61320
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7A 10672 bytes
font_02_sfnt_off00010480.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10480 16792 bytes