Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bcd48f5464c1999…

MALICIOUS

PDF

74.8 KB Created: 2021-08-01 02:50:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1d19d14eebd93524feafe1d282e6d8f3 SHA-1: e5dee85c955ce644b0db9fbaf634397f4735e043 SHA-256: 9bcd48f5464c1999b9c402dfb4ce30fb3021234d91bdddcb6e3207f61569c253
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, forming a link farm. The ML classifier also strongly indicated maliciousness. The embedded JavaScript likely facilitates the redirection or download of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 8

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://homeopathyhongkong.cn/files/83482107296.pdf
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/4sst3gaso70seo6vnd7nku8bk4/bujomenatirufatut.pdf
    • http://factblogs.com/uploaded_files/userfiles/files/42042853569.pdf
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1608190e3e7c83---39998954154.pdf
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/cc9f31ce1a1ba554306a3358da9ac654/sukufibadixufifewegoremi.pdf
    • http://perfekttorun.pl/pliki/nuwaf.pdf
    • http://omg.su/upload/File/73377323484.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/doti358vtnrkdmkr8volu027p4/85029135021.pdf
    • http://gold-carsales.com/js/upload/files/kizika.pdf
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/aphiukuv8uua3f2vlvv2tmq446/fomukajixiponugisexax.pdf
    • http://hifitness.hu/userfiles/file/zevotijoxutop.pdf
    • http://indago-rovigo.it/userfiles/files/fidigiw.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a842da28a34---wijaxafetixisokolexu.pdf
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/5a7c80d87fdbde32a2d5a9bdec4c639a/jebadibefotapevadiredo.pdf
    • https://bataretak.com/img/files/file/77024656126.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16088079f1c734---dubetoko.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/sstovencmb9r0b8qn3vmv635k7/86746291899.pdf
    • http://deckdreams.ca/clients/3/34/34055ef41782f8f15ebf372c1e39ecad/File/mizejomavuseramagelive.pdf
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b20b856e3f---kegizazovuverunuzozesu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+install+xv2+mods
    • 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_off0000c3fb.bin
8689b07e6c2010e3c7ebb48042e686706a6e0fd56030d4cf4a5bfb07c0f482e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xC3FB 16464 bytes
font_01_sfnt_off0000edd7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD7 16792 bytes
font_02_sfnt_off000105ee.bin
8becc30e327d900fa502dd9eaa7d62ef400ddb8e7608467c3262cf228eadd3ee
pdf-font-stream PDF embedded font (sfnt) at offset 0x105EE 10544 bytes