Malicious PDF — malware analysis report

Static analysis result for SHA-256 141127c950a69375…

MALICIOUS

PDF

92.4 KB Created: 2021-07-06 22:43:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18d23591b10995f6c250ff05bfa366ec SHA-1: 14cea7c94575b5e947f496522214ab8d4744d269 SHA-256: 141127c950a693759b6fbe0c532fdeea395c91c3bc2714d885a1e32bbcca5031
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to potentially compromised CMS upload storage. The embedded JavaScript likely facilitates the redirection to external URLs, which are numerous and varied, suggesting an attempt to distribute further payloads or conduct phishing. The presence of multiple links on disposable hosting and compromised upload directories reinforces the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://meteosputnik.ru/userfiles/file/85052319928.pdf
    • http://maezawa-jidousha.com/js/upload/files/10430617504.pdf
    • http://studiorinaldibedin.eu/userfiles/files/kowufajolaxadivikomu.pdf
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160d85731da71e---zevazuparini.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073b4d168efe---tufezuzubebupuda.pdf
    • http://vmkmsz.hu/userfiles/file/vitenigomidol.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0edce3a56---31745448635.pdf
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/lisawojuzefasakis.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c315cce0674---nanixetegi.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a6292e61f17---mubobezezovakexofapofiri.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b83b73929b6---61188982623.pdf
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/18cc4ecdc8fe790d1fa249cf56db8ba4/31862742196.pdf
    • http://applexin.com/ttpsea/files/file/94417681448.pdf
    • https://appchecar.com/ckfinder/userfiles/files/6673575245.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c69ffeed16f---sopapitusozez.pdf
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/3e0c0a23373fea3977d8cf413040e274/xifujijanugulofi.pdf
    • http://arenabilardo.com/data/_files/zebiwunagixupunubabopore.pdf
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/77945572521.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c947f5ca9af---mageg.pdf
    • https://amatnieks.com/pictures/image/95785458374.pdf
    • http://anthonyvienna.com/sites/default/files/file/buparexoxasolijijesuzejet.pdf
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/f1f7b918bc52c8d66317aa2599e660d2/milupilujuzumofajute.pdf
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/16080b5f963499---15685105619.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072d5c506bac---mokokolikilupenarinupujix.pdf
    • http://botosani.ro/img/uploads/file/somoduzewome.pdf
    • http://sam-global.info/files/file/39167503886.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=hybrid+seed+production+in+chilli+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_off00010405.bin
623b313b2a1fb345b49c1da384c3260a6d5e3b5e58b9d714382a70a12383a4a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10405 18020 bytes
font_01_sfnt_off0001335c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1335C 16792 bytes
font_02_sfnt_off00014b73.bin
491219777321cc139c708f1b0f7bdcb57c792f08489b26f68aaaa37a416d64bf
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B73 10900 bytes