Malicious PDF — malware analysis report

Static analysis result for SHA-256 c18f35b51c533ec2…

MALICIOUS

PDF

85.5 KB Created: 2021-07-12 22:15:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 26c888742f0c196b7e70194348a4f4e2 SHA-1: 372325e35aade46606a9f80aabc26b03c704b50e SHA-256: c18f35b51c533ec28e0328789c017f3890a43c936f0163000c4b7f46698d4df6
196 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a browser extension installation lure. The PDF contains numerous links to potentially compromised WordPress sites, suggesting a phishing or malware distribution campaign. While no scripts were directly extracted, the nature of the lure and the embedded links point towards an attempt to trick the user into downloading and executing a malicious payload, likely via a compromised link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607447a5080c6---wosijus.pdf
    • https://ises.ca/phpsites/vertical_living/uploads/file/genetufibulitijopagawi.pdf
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/3eh6d9055j3pc9knv2t455p3e0/fafopakujigixape.pdf
    • http://ucity68.com/clients/e/ea/ea220da86df44fb0ae3b7c8e8295ccc1/File/sefigamobisowakapo.pdf
    • http://extracam.es/app/webroot/arxius/file/82911167881.pdf
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c41117ca3dc---gukuledidarosud.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/4cda508bb0be48d1c1fdf918e78a9c7d/vizebexisovibomuziki.pdf
    • https://stomatoloska-ordinacija-rijeka.com/files/vibozutonekidexoxuwotowi.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/ad8d64947cb83fd30692cac0844961c7/8337520356.pdf
    • https://motelandratecuci.ro/userfiles/file/militanefozidalef.pdf
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/sdbcjae6op1bd9anra48h96f9r/dodavimexaguxovusatiz.pdf
    • http://gtshotel.it/images/file/todalelopitelobarewufeza.pdf
    • http://kulturazebrak.cz/userfiles/1032647466.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b878ac238e8---98978116118.pdf
    • http://valifyrepapillon.com/clients/6/68/68e1c6a84db99a04c21676ff826d6e37/File/65793207676.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b37bf715b0---numovu.pdf
    • https://feng-shuiworld.com/userfiles/file/sezefumitelakarot.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607373db0e288---95370581384.pdf
    • http://naturallabs.fr/userfiles/file/giberatumu.pdf
    • http://rana-international.com/userfiles/files/jafiwas.pdf
    • https://okazdedziecko.pl/_files/Media/file/taganosijelopeveluto.pdf
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/53694301071.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac65909cf8---zawesoxofe.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=when+do+you+use+an+in+a+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eca4.bin
0264d404f8db41cf4f02fd8fac3cc8017c01b968e11707e369ed24f6486500d7
pdf-font-stream PDF embedded font (sfnt) at offset 0xECA4 10528 bytes
font_01_sfnt_off000104a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x104A6 16792 bytes
font_02_sfnt_off00011cb8.bin
0bb2e2d5248da08f5a0982ac5777ee5f7bfc5c21765f26a7f9a4007eeb35e5b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB8 16828 bytes