Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ff160efd0736890…

MALICIOUS

PDF

82.9 KB Created: 2021-06-25 21:14:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8e31ca162ecb17c7d97a67c61fd1d65b SHA-1: b1a154dcb98553e6d43a1985162941c875d33ac0 SHA-256: 4ff160efd0736890d6aafd70c4ec8e49f72340c0739989b3247aa56b98fd1bf7
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 http://topupdana.com/contents//files/jafafebuzapotovonaf.pdf
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/54d91fecfb6db5ecb06dfc744345e1e7/porovebimevepadopajazo.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/ir2cf1i5d1gafa6qsqd24qllj9/rananipikasizigoniw.pdf
    • http://446888.top/userfiles/file/72849697365.pdf
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ed1e9bce22---tebebozumavumuxelolije.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/e7e79712498f38bcba34bd4e88afeb0d/wudopori.pdf
    • http://fresh-j.info/images/uploadedimages/file/94433190626.pdf
    • http://asesorgubernamental.com/images/file/12278124970.pdf
    • http://jaatkinson.com/userimages/ziresa.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c0fad35c963---mubuwekobiwafos.pdf
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/0ded3590ccd42e20608fadde850a6037/47715624678.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/e7e440d17be7d9473ce69e7ef6cebcfe/sowomodapinurewodu.pdf
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079928fbfca8---jefurudito.pdf
    • https://ivaco.it/file/48186637711.pdf
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/ko0cmhlu2qre5aboik0co88p8h/pekemolatojamenememomupi.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608edb9b78efa---wukavazelemumuwenezi.pdf
    • http://heldermusic.nl/ckfinder/userfiles/files/fevoxiridewitegegazudik.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e1238d5e16---taxudixomanetaxepovibubo.pdf
    • http://stlnsk.ru/uploads/file/92694248736.pdf
    • http://dharmapremipariwar.org/userfiles/file/86158018129.pdf
    • https://divinesacredshakti.com/wp-content/plugins/super-forms/uploads/php/files/3c58c713e5578120cf2547e5d0a0986d/kuxiragabinexesufodejep.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=malthus+view+on+population
    • 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_off0000e284.bin
e1ccdbfb78597c71b89ccdf2ab25b0a682b46177a9a84d9ec810e2867632e102
pdf-font-stream PDF embedded font (sfnt) at offset 0xE284 10496 bytes
font_01_sfnt_off0000fa64.bin
766a0182c98d92c0172c333199d9cf4954b77d2497ae7067a3a582f29c8aa0d9
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA64 17120 bytes
font_02_sfnt_off00012674.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12674 16792 bytes