Malicious PDF — malware analysis report

Static analysis result for SHA-256 141fff13e8aacd53…

MALICIOUS

PDF

106.9 KB Created: 2021-07-21 06:41:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 86ed8e34d5204f137bce11ccfc1d0477 SHA-1: 31b10e86f14fac5b53bafb0ef69333949347d13b SHA-256: 141fff13e8aacd5338e6219dd0f284ffb421913699b72422d8ff24bb26ba8d96
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. The primary attack pattern involves luring users to these external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 6

  • 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.
  • 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://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec4f8a97ac---8154330218.pdf
    • http://donationwebsites.com/clients/6/68/68901b9e08e997a22fc64c74502b39ca/File/xabuberalogus.pdf
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/q5frp44jh8h4lcv748gu7op8d6/garajanelerazepesiji.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/0b5c5de0be428ae86ec8bde0f906a92c/vejopazutosisinemudup.pdf
    • http://aps-mes.com/files/file/zakep.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e7e4880fbf8---79225707195.pdf
    • https://cornwallstaffagency.com/userfiles/file/vujuzavukisisiduvig.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160b574e24df3a---monanuzinas.pdf
    • http://wamer.org/userfiles/file/1621369022.pdf
    • https://ferado.vn/userfiles/file/xovatutomuge.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/5eee77344d8cc1a6fd7bfa4038630d5c/8154334314.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/3979b6e37e4c2bce6b824089ab11ef96/filonasaz.pdf
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/givedatirosigitenozizuv.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba3ffd2ba0d---kolewamuvazin.pdf
    • http://tano-cable.com/d/files/44828054507.pdf
    • http://asea-admin.com/_userfiles/file/20210507141730.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/d4081f3183a291ec829d5f093f6ff92f/42591385404.pdf
    • https://clubsecurite.fr/webroot/upload/files/nubititazozotaku.pdf
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bepiwazotexewiwasafakina.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077c246d003f---36211993579.pdf
    • http://shs1977reunion.com/clients/41590/File/vekibibiwamuzol.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=faster+movie+actress
    • 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_off00013e8a.bin
91cd313385db3883da6e577a50009023268c61c062a326a054dcb96ed53f8da9
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E8A 18132 bytes
font_01_sfnt_off00016dd8.bin
4f4ac99f633629b1e2babd58d957489c889c4eeeb40b94d2e728e16e625b5061
pdf-font-stream PDF embedded font (sfnt) at offset 0x16DD8 10284 bytes
font_02_sfnt_off00018516.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x18516 16792 bytes