Malicious PDF — malware analysis report

Static analysis result for SHA-256 7961ec76ede2aaa7…

MALICIOUS

PDF

75.8 KB Created: 2021-09-26 17:21:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 97026bfba3f2ac84d36afc8a291a2a90 SHA-1: 2d080086365c86eb519fc297594710806737b287 SHA-256: 7961ec76ede2aaa76797aa9cdb6f423f696d3b84102d2f31507ede56976284ae
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for delivering malicious payloads or redirecting users to phishing sites. Several heuristics indicate the presence of link farms pointing to compromised CMS upload directories, suggesting an attempt to host or distribute malicious files. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145a2e293b7d---74694474435.pdf
    • http://imbirimbir.ru/files/wunifoliwajosugode.pdf
    • https://jagamimpi.com/contents/files/diziworokamakoxud.pdf
    • https://datatalk.ilvzhou.com/upload/files/2021/09/202109041851121036.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e7a26f32d4---52498766180.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ccfa32f6af---vonelowemo.pdf
    • http://ky-auto.com/uploadfile/files/dutidizafujudekurotobuz.pdf
    • http://goldstecq.com/userfiles/file/lilebamivenefefibi.pdf
    • http://rama-sp.com/rama/webroot/js/ckfinder/userfiles/files/wesasawunapixanutinuraxu.pdf
    • http://chetaomaynganhnhua.com/uploads/files/sobol.pdf
    • http://virtualcharityevents.com/vce_cake/files/files/segatulovimijofu.pdf
    • http://emilybarnes.com/DEVELOPMENT/VERSIONED/emilybarnes/trunk/sites/default/files/file/77923814620.pdf
    • http://nomayaku.com/userfiles/file/70539640965.pdf
    • http://koryosushi.com/uploads/files/57149159703.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161343ce4d4e5b---48791983600.pdf
    • http://mistral-paints.cz/userfiles/files/99905254731.pdf
    • http://eur-idea.com/userfiles/file/46630480761.pdf
    • https://ltes2.tw-goods.com/UserFiles/files/3987139082.pdf
    • https://www.rongoldmanlaw.com/system/js/back/ckfinder/userfiles/files/69402610776.pdf
    • http://clinicaveterinariagussago.com/userfiles/files/mofabelujopepebakagigo.pdf
    • https://lemarko.com/userfiles/file/kumavuke.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1614c9d066120c---98153308168.pdf
    • https://economiadecomunion.net/ckfinder/userfiles/files/2107101100.pdf
    • http://robedecreateur.com/img/files/jadujiginigixisobazoxixa.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16142597521c45---seselasibuxu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=paperboy+book+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_off0000c037.bin
8828ff6b1047bbc0f5a2d7cedc282216c3974a2841746e3b7eaf6a8bfcebd391
pdf-font-stream PDF embedded font (sfnt) at offset 0xC037 19428 bytes
font_01_sfnt_off0000f296.bin
de6b56d181f4a2084b4886757f4798b56e0a360c2c34e39f92b4c7133896ceee
pdf-font-stream PDF embedded font (sfnt) at offset 0xF296 10328 bytes
font_02_sfnt_off000109d1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x109D1 16792 bytes