Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f6963a03b9118e0…

MALICIOUS

PDF

89.0 KB Created: 2021-07-27 16:26:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f6381e08659d2578c451928518ec938d SHA-1: b9cc0656fd1a0f00edb46a12a0e79bdf2bdf8a9d SHA-256: 8f6963a03b9118e032903583ebf2aef57766d5c53e10b1b67e974538c096fe04
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is often used to exploit vulnerabilities or redirect users. It also hosts a link farm pointing to multiple PDF files, some hosted on compromised WordPress sites, indicating a potential phishing or malware distribution scheme. The ClamAV detection and ML classifier strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://tndgdemo2.com/ckfinder/userfiles/files/71749308321.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe00591082b---rulebi.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed0d7188068---risevegukigufodo.pdf
    • http://healingtown.org/userData/board/file/konuwozevumexirup.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b50fa7a04a---18281467713.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160817524ccc72---wimawobizowilez.pdf
    • http://atomleasing.ru/media/File/45348072274.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8f91cc4a1---19764345854.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ab7dee3db---72013771299.pdf
    • https://drsaman.com/files/tekelilasepusiganodali.pdf
    • http://niestachow.pl/data/aktualnosci_imgs/file/64457804158.pdf
    • https://bamfieldrental.com/userfiles/file/69428708457.pdf
    • http://veraschwemmle.de/fckdata/file/tixubigufexe.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/e8d2162046d0738a12ae5ec9fa86d912/53220865831.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a50344780e1---wasowupazolufobiwavimalo.pdf
    • http://andlupa.com/userfiles/file/56764588984.pdf
    • http://zoldjogsi.hu/uploads/files/wanadekeluv.pdf
    • http://dalaichau.com/files/farisupomabozom.pdf
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160725f7930c81---tefagotuzefivoxaz.pdf
    • https://csn-alliance.com/data/files/zenivake.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cad8e40111---pulaj.pdf
    • http://classiccar-jp.com/js/upload/files/fogelemigebijin.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ced1e186d6---nidoxesigajorar.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=how+much+are+standard+wire+haired+dachshund+puppies
    • 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_off0000f4a4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A4 16792 bytes
font_01_sfnt_off00010cbb.bin
cc656b0e75536ec82e9155c66feebc6fbffca36a7dbf1222aa93b635665a670f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CBB 10912 bytes
font_02_sfnt_off000125d5.bin
ef7dbfb6913e044970fda02e4346df0bd063814a525692f14715afead076e68d
pdf-font-stream PDF embedded font (sfnt) at offset 0x125D5 18284 bytes