Malicious PDF — malware analysis report

Static analysis result for SHA-256 c19bca4526bf820d…

MALICIOUS

PDF

85.0 KB Created: 2021-07-10 04:08:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c592bf864ad3557784e965bd0bcfd282 SHA-1: 2d8cfe9267ad8773486bf629ca65de3a6bb8ede5 SHA-256: c19bca4526bf820df81b62c9b0b130c1cff377676cec94de9ea13b59ad3facd7
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO poisoning to drive traffic to malicious sites. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://stardentalcare.org/userfiles/file/95031157305.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c1ccda7a6f3---64465324754.pdf
    • https://sluganarodu.org/userfiles/files/45792410696.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16090333a5e33f---51863280345.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16095c2802a1b5---72341779293.pdf
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/f78d7832389b26b727efed35b0d01869/xanamepofab.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ad0bf3428b7---85095484720.pdf
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af23b508b99---43448695815.pdf
    • http://braciszewska-klimek.pl/fck_files/file/kalajemutudirofuxosala.pdf
    • http://www.asslar.de/downloads/kikomadufojevavepalekimuj.pdf
    • http://fluidearthconcrete.com/userfiles/file/rijutijiluse.pdf
    • http://tdbakademi.org/userfiles/files/15652548937.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ad4228b91---49992194932.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/eli1dlh9dj8149vunnib8s7bv1/88701763217.pdf
    • http://intergeored.com/upload/File/fijuzulapotukatabomuvu.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160852dd8e0940---likil.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/7mccjq7cq2pu41s9896bombq8j/41607882252.pdf
    • http://baheth24cars.com/ckfinder/userfiles/files/junojegodozivozojufalix.pdf
    • http://se-ty.ru/uploads/userfiles/file/26204264148.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/5236a20efaac2488a87d4f79577aa653/73986622534.pdf
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/1j9b12ki57k5q8blaro352jiup/sorijedogejoxobonelam.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094939f4a0ca---bikazewuzelebofedep.pdf
    • http://pamatudarbai.lt/ckfinder/userfiles/files/56308356457.pdf
    • http://thomasbelldescendants.com/clients/40432/File/92265122307.pdf
    • http://halongbaycruises.org/upload/files/46964331001.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=starting+a+body+paragraph
    • 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_off0000eb4d.bin
599a7fe0213bd5eaf473ce6849ba05818f1d4267f88eb596acf52aa5ebabc758
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB4D 16780 bytes
font_01_sfnt_off000116f0.bin
e5ff8e493707b618ac5203897263348859526eb22d754be89ceef3682cae56ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x116F0 10652 bytes
font_02_sfnt_off00012ecf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12ECF 16792 bytes