Malicious PDF — malware analysis report

Static analysis result for SHA-256 c116a789c8ae513d…

MALICIOUS

PDF

73.6 KB Created: 2021-07-07 00:32:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3b428ade6533b96043b694db8c3f250d SHA-1: 4011062afcc4b7bf85ca7f978e178e609c67c2ec SHA-256: c116a789c8ae513d97656082133591125d24d8bfa66c3bd45598105f47321e84
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document exhibits characteristics of a link farm, with numerous URLs pointing to compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the presence of multiple links to potentially malicious content suggests an attempt to distribute malware or conduct phishing. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://ctkupavna.ru/upload/file/91487218405.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c33252eed---bozidokujanukapit.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b441be841d1---wegamituvujatanilukisoxa.pdf
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/95048dc7202f7b083992f9b1de498a7f/3439615993.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/fbf2092e720564a76fb7a09ef5de5946/23844076866.pdf
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/fabf500e75559bfb78ba4047251fde44/jositepawa.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/1107c3153b9a6b3b6508cf67d439ab6d/73727186174.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3e83d4ac9---26039915029.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160945317143b2---nexetazarasuw.pdf
    • https://path.mn/userfiles/files/jilodi.pdf
    • https://stef-nancy.fr/upload/document/50707299615.pdf
    • http://antonioruizabogados.es/userfiles/file/tonuvi.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160c11c9130f9d---xerezafavamewujukopu.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/oia6hdcsbchh8bqmg8h8o7bgp1/gusidav.pdf
    • http://alkalacarservice.com/public_html/userfiles/file/24269915792.pdf
    • http://menloathertonhigh1980.com/clients/6/6f/6f83464fe0b13873896cace574d4baa5/File/matijerejut.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/8586e6ab87c5a4962dc662e2096f11a3/tazowojelodorili.pdf
    • http://www.aadhar-interior.com/userfiles/file/51550265890.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607137da022da---dafexufib.pdf
    • http://innotack.com/userfiles/files/53819742282.pdf
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/5abb3acb151ba37c5a247112e7471fd9/38610135085.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606d39edacdb9---86725084943.pdf
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/8042fda120cd278fbf0a0abd1b20ac15/zuwajikasoxobafojobinaped.pdf
    • http://beloit1962.com/clients/8/83/8368a4f838dea3176655029ae9e337da/File/refezepidodok.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=default+size+of+arraylist+in+java
    • 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_off0000ba56.bin
9b507967fa5d48b637ab4d838a9b731a961f2235863c3d2323bd7726c3faf484
pdf-font-stream PDF embedded font (sfnt) at offset 0xBA56 10680 bytes
font_01_sfnt_off0000d2ff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2FF 16792 bytes
font_02_sfnt_off0000eb11.bin
ad5672df0225a30a833e0ded06c7782b718de98dd0bafbdefc68f1996f6b2968
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB11 18088 bytes