Malicious PDF — malware analysis report

Static analysis result for SHA-256 43a0aef68e7b8182…

MALICIOUS

PDF

86.8 KB Created: 2021-06-26 04:38:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cefb960ca124ebf66ae75defa03680cb SHA-1: 123917b4ccc1d978eceed51280c5b9509432e35c SHA-256: 43a0aef68e7b818234480c10a7906df6fa45b8c4f071f37d099275484523d444
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple compromised CMS upload links suggests a pattern of using these sites to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/ef2b56f7aff4a63ef4bb8f977234795a/36591609491.pdf
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094cc1623271---14229083530.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fb17514574---52693299728.pdf
    • https://maturana.cl/upload/file/25969826976.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/f35aaef4c5c452c1e7849d7c3bd164c7/91192750539.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16087476399085---nejotolin.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/54d0e1c3163a6a698b96705ec8d647be/lorikevaru.pdf
    • http://agnieszkapawlik.com/userfiles/file/kosejokoxulemebosigupomu.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16075bcf23fcee---kujuwuz.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd0a2880290---gurabikiwezibexasimidonu.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160acdc966339d---zuvuko.pdf
    • http://camionespanamericana.com/userfiles/file/90998987233.pdf
    • http://byty-pardubice.eu/UserFiles/File/83618679702.pdf
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/84kbusdnq5185ctiilnrfpfn94/vitafabapasubojoxiboz.pdf
    • https://bangprice.combangprice.com/beta/cms_image/file/dukejoguvupazimufigemave.pdf
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/51c1597cab8ff86342359a59c6fca70f/nebenipifovodexiga.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce738e5569b---tedewuj.pdf
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bb521c45f9a---69744028796.pdf
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/55aeaeafd387c23dcc49e1ef1b278c72/97927141797.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16088fae8630fa---mikobixasiraxugeto.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=praise+the+name+of+the+lord+our+god+praise+his+name+forevermore
    • 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_off0000e836.bin
712f7c0000da8d4bf95ee5c481bdd3c7aca66a4b4e4de0e670778b451eba47c7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE836 19084 bytes
font_01_sfnt_off000119b0.bin
6cc97441e763ca93c5e9ff2cabb6a4effcb775170a79adfd09f7b2f78b619101
pdf-font-stream PDF embedded font (sfnt) at offset 0x119B0 11112 bytes
font_02_sfnt_off00013339.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13339 16792 bytes