Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac4a4c412193a00d…

MALICIOUS

PDF

91.6 KB Created: 2021-07-20 19:32:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3398c974ef5f3f862efff4ded89092fe SHA-1: 004f7bd0fc60b2c7c1369c6430e6b98e16a1c675 SHA-256: ac4a4c412193a00d0cdcab374cf0eb5ccd563d882be141e2402a2bb41436ac1b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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://viticoltura-enologia.com/file/90200523297.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f14e3a723d---xefujetopimor.pdf
    • https://dynasty888.com/image/files/20210606_234401.pdf
    • http://khonggianmang.com/upload/files/xezolokajumezudawifapowuz.pdf
    • https://newtech-utm.pl/userfiles/file/64208764118.pdf
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/adbad6cb30907a3eb601137b5dbc4af6/werupibironogige.pdf
    • http://guowangcable.com/d/files/bapevawiratile.pdf
    • http://pneusmarene.it/images/file/kejamubozid.pdf
    • http://ncabhsa.com/clients/875427/File/badetadoruxar.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-5-5/20210505100219248208.pdf
    • http://www.bash.cl/media/file/rarap.pdf
    • http://nadiadsa.org/userfiles/file/10136661293.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/lfqehs44hr5pcimugu3510tnoo/nasudon.pdf
    • http://carroll1975.com/clients/4/4e/4e2b018d07aaa5a30c3e4fca1c7a8df7/File/84987786944.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/1e520ea0165d24f521d08233b33fd72d/panesuwiroxe.pdf
    • http://mitcostruttori.it/userfiles/files/labirolu.pdf
    • https://uleshuzataruhaz.hu/files/file/jutonobizidat.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f6d22bf792---fapubijofabapexazovize.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606efc6f39485---todose.pdf
    • http://alliance-vietnam.com/upload/files/bokogevurapixafalibivevo.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/f4bf77438d40157bff2029210ae05494/funapusajefeb.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/u0j002n46l6joia1fbjtmb7h73/gexoguxunowexelibov.pdf
    • https://arhometutor.com/userfiles/file/98461799555.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=changing+declarative+to+imperative+sentence
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off000130f1.bin
c98283ed137677a5f2d34b2791b76a36c59a9494d32583cfa1f2e5c7153b973e
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x130F1 16888 bytes
font_00_sfnt_off0000ea58.bin
e2971aca71b688dd683be8a45b83a408995411962f51a4ef813c8e653774919c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA58 17432 bytes
font_01_sfnt_off0001178d.bin
d2f2ae11e59eea62784e2dfee0e01735a65745483c96c32f370331550d138032
pdf-font-stream PDF embedded font (sfnt) at offset 0x1178D 11056 bytes
font_03_sfnt_off0001494d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1494D 16792 bytes