Malicious PDF — malware analysis report

Static analysis result for SHA-256 611099c8a11a0754…

MALICIOUS

PDF

93.7 KB Created: 2021-07-07 16:59:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d2324c3a2e564f6113041ec2c8b39d66 SHA-1: dcdd78bbaac4aeb1d7f88eb525cb7fa5170260b4 SHA-256: 611099c8a11a0754b339bba8ef6d079829c58a9af10b73e1444b1f17e2714146
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. Several heuristics indicate that the PDF acts as a link farm, directing users to compromised websites hosted on disposable domains, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly support its malicious nature.

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 https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826328b3943---tiwugawojizedupana.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/cspsn9degn251vboiapj1m19s7/gaxorozit.pdf
    • http://polesprogettazioni.com/userfiles/files/56007673477.pdf
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1606d552a7f02a---23183198837.pdf
    • http://avandcie-automation.fr/ckfinder/userfiles/files/99586869319.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/116a9a2aa0e1250d7c3e8311546d06bc/17190075317.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16083b0da3a416---99040707628.pdf
    • http://kaizousha.com/js/upload/files/52944726455.pdf
    • http://snsi.jp/image/news_file/karusagegivaziwobatekaz.pdf
    • http://camonetinternational.com/files/file/70260311873.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/tvfl0qn5d3796qm235kjqu5g8q/93820588660.pdf
    • http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/56333399575.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160b2dbeb90402---zekugaxano.pdf
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2702049b7d---daluxitimisudebegivuzulo.pdf
    • http://homeopathyhk.com/files/wuburitiruwipivelolemi.pdf
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/f2lhm07cquabkeqhonica80lu1/45512643367.pdf
    • https://limmaginebistrot.com/file/35001058255.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607d64060596a---40895101218.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608871db0aede---66830120435.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160adfd7e6a3a3---wenepon.pdf
    • http://goldartline.ua/userfiles/file/vapij.pdf
    • https://detectiveoffice.net/userfiles/file/9094477930.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc33c4c24a---77370346188.pdf
    • http://austral-immo.com/userfiles/files/11721927327.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=family+analogy+of+the+cell+organelles
    • 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_off000106db.bin
eecbc5aff956c57ef1ad267d2ec8cdfc7d28d2dff76474351df66d39abc5cd0a
pdf-font-stream PDF embedded font (sfnt) at offset 0x106DB 18632 bytes
font_01_sfnt_off000136de.bin
44c4b3ba0bcefebc07f8fc9873f4be42e368e04014d815ef5fb5f5fa353d4d0e
pdf-font-stream PDF embedded font (sfnt) at offset 0x136DE 10876 bytes
font_02_sfnt_off00014fd0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14FD0 16792 bytes