Malicious PDF — malware analysis report

Static analysis result for SHA-256 be3985535310ef86…

MALICIOUS

PDF

75.2 KB Created: 2021-08-29 16:10:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d7d49ddc278849582bc49519396200f9 SHA-1: 8efbd947a2e47375920fb528052a885244861c4c SHA-256: be3985535310ef8662b6be64016e5057a68089ae3c5d4c10aea9aaad094ac23b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm with numerous URLs pointing to other PDF files, many hosted on domains associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct user-facing content to analyze.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://backkwang.com/userData/board/file/mivopibe.pdf
    • https://strongpointmarketing.net/userfiles/file/99842645330.pdf
    • https://cantarefides.ro/admin/userfiles/file/gijinenevipowi.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/09q8drgecosb6t11579c259scl/jovumelolosovunevitiwer.pdf
    • https://www.douggoodkin.com/admin/ckfinder/userfiles/files/39195187206.pdf
    • https://euroroma-bg.org/files/file/29209057725.pdf
    • http://aucoindeshalles.fr/menu/file/84002550228.pdf
    • http://fitviewer.biz/files/file/lusewexef.pdf
    • https://feldmann.pl/userfiles/file/kodewigoxafizuzara.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/7cpqvnvk4rcqsa2os81m0k780t/novavowepafusiluxu.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ff3025d1d---31374889383.pdf
    • https://churchboys.org/userfiles/files/bimoziwad.pdf
    • http://tindangnhadat.vn/upload/files/93919031373.pdf
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/26f4a1a95477a7da97ba4cc28d364b04/nuponab.pdf
    • https://sofupingame.com/calisma2/files/uploads/3541002294.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb4e2efa34---39058548590.pdf
    • http://namkhoabacninh.com/images/files/50073258423.pdf
    • http://bakerfamreunion.com/clients/1/13/13be4b03bdabdd3a133c3ee64ed6201b/File/kerugelazoxavowekapuv.pdf
    • http://embeddedhr.com/ckfinder/userfiles/files/78994651162.pdf
    • https://hkbca.org/UploadFiles/file/20210712220204181.pdf
    • http://flomojapan.com/upload/files/zitelixonaletomot.pdf
    • http://przychodnia-felinskiego.pl/uploads/editor/file/jujadubumaxorab.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=cross+your+paws+rescue
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/d977ac4e23573b68047b423eae75bc08/23208086663.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_off0000c37d.bin
4d693a3397bbc1ed57e7fb70e38943fd86b7d22fa89b3849f3ad4cbb1a8a8de5
pdf-font-stream PDF embedded font (sfnt) at offset 0xC37D 10356 bytes
font_01_sfnt_off0000db1e.bin
851ea7ca8308cc7378b67c30f9afc4dd1d674f890c619edb5e37c1df4afec077
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB1E 17116 bytes
font_02_sfnt_off00010736.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10736 16792 bytes