Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac93d4a6099c036c…

MALICIOUS

PDF

84.0 KB Created: 2021-09-02 22:18:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 499e27ebecd9966ed50a499a0f46e47c SHA-1: dfcb2ade2f2c664f102b7fb68d9762ff595ee558 SHA-256: ac93d4a6099c036c79a087ab38abc42094c4b1a3ec381f5433ee81b11d683a38
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates that the PDF is a link farm on disposable hosting, suggesting a malicious intent to redirect users. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • 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://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608df445520b4---komimareminaxarivojomoz.pdf In PDF document text
    • http://alnoorcity.com/userfiles/file/pixababirugesiwitaramak.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612173ff3df05---75134243118.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/8ofd6vlgf67a2s5dp0q2vrgj6t/rumagetafenilenar.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/e3cb4b82ed5f5610420305b7d988abc2/zusagixixebusonenurapedar.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/16036876495.pdfIn PDF document text
    • http://eapver.com/upload/ckimg/files/202108142222539949.pdfIn PDF document text
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/wopikugepefibu.pdfIn PDF document text
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/572832a1118170a22f924bf575f1016c/dajejita.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/ditota.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/fff95c13efcf32a775c3ad651f1cb5c4/monusodofelilexo.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/8l629v85cd2c5egb1fvl1fvg65/59769203218.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16070d636b9155---muwababuzizoli.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/4a67ffbbb805f22d3a31cccd0f3e124e/22072403455.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e342fc0cb3---63782919217.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc3bcd880a---3303718159.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c20b6541ab---4503897875.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/t5ls9nafrjhuutnsifgk3osm0b/89629354713.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a2007b8f710---bupepulaxiwugerolu.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/razasavofuri.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/5in7uhng3sj0algpl7alsegto8/xisenejedopofepo.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/67329955221.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=honda+fit+hybrid+2011+user+manualPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE162 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f979.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF979 11260 bytes
SHA-256: 248748c8ad4903deae04987805f94c406462b8e1240ea3f705a8b584223f9e35
font_02_sfnt_off000113ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113BA 17812 bytes
SHA-256: 88c8f7c46f9885f5032bee9a2dac6fc9a37697410092aec31ff01482a927971e