Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f3f4608eb14caa5…

MALICIOUS

PDF

83.0 KB Created: 2021-09-18 14:59:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53527999ab6b7c8a65de2b10966d7fda SHA-1: aadc0bb3b095efd268f97f83ac8ddecd07846699 SHA-256: 7f3f4608eb14caa5c772837138366b5617a548a95ce8c976fd7a7bd7d281b7dc
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also contains numerous links to external URLs, many of which point to compromised WordPress uploads or disposable hosting, indicating a likely attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly support its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://domesticsolutionsagency.com/userfiles/file/vasonowizefuvomapi.pdf
    • http://potlista.com/file/files/67849399969.pdf
    • http://tcsklife.com/filespath/files/20210910120259.pdf
    • http://logtech.cz/foto/Image/file/vesaluzemonaluji.pdf
    • https://mkserwis.pl/userfiles/file/86058076896.pdf
    • http://alituncer.net/userfiles/file/2464192535.pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161374ae54e18e---41136991211.pdf
    • http://inspiredindianfoundation.org/uploads/vesowelibixi.pdf
    • https://ambulatorioveterinariosismondi.eu/file/93112525551.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142bb7e87a27---14504865547.pdf
    • https://ecpa.fr/uploaded/file/37238085008.pdf
    • http://zussobrance.sk/grafika/dokumenty/raxegivajivaxogox.pdf
    • https://cafeau1ait.xyz/js/ckfinder/userfiles/files/57342075923.pdf
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/253e6a71bd9abb685da1b1999fa6220c/sofupenusomu.pdf
    • http://shiinamotors.com/js/upload/files/gagalimigib.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/161330f37cb1a3---73424010042.pdf
    • https://kvizek.hu/ckfinder/userfiles/files/9929562200.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=the+fiery+cross+read+online
    • 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_off0000dff6.bin
785b7b1400fd6d741363519197c977c8bcad73398225c6196c77ce84b1a5b3e2
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF6 10552 bytes
font_01_sfnt_off0000f7f7.bin
ad694ce59faf43061df65f119f2368c83f7694ec48b3611dc748ccb48c6d187c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F7 18208 bytes
font_02_sfnt_off00012730.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12730 16792 bytes