Malicious PDF — malware analysis report

Static analysis result for SHA-256 96731f19eef0e31a…

MALICIOUS

PDF

90.7 KB Created: 2021-07-07 19:15:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9a6a97f82bcba2d3b6564188c1132f82 SHA-1: 8569caf3e0e7b4fc46fca77f487e240861ffdaeb SHA-256: 96731f19eef0e31a5415a2feabb7a2f8807e1c9e7fcfd3bcb007241482c9ca3b
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised websites hosted on disposable domains, likely for phishing or malware distribution. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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 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://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/428f185a23076d2f874a3f5c4f884558/lubopozulavilov.pdf
    • http://dashoernerboot.de/userfiles/debokosebaniwo.pdf
    • http://mini-garden.ru/userfiles/file/88442634997.pdf
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/63f7d1717de4e3e8c14ab27f26fdcd74/46356965135.pdf
    • http://brenna-ski.pl/userfiles/file/50517068055.pdf
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f57aa62f6---42502247054.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcd4cacd820---xamosidaguzubutovan.pdf
    • http://asupuro.com/user_data/image//file/gukudamefesixezibedi.pdf
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd5c5b2efe6---kifidopajerirituwifobefej.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/b7uoor2hteegv6p6d3mi1olv46/dibogixekovegokutizebetuj.pdf
    • http://ahlhy.com/uploads/file/271936258336.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/58bf7788f95c0a69c6eac2c32465d41b/30106407641.pdf
    • https://shellserva.nl/docs/Image/file/regapevomunoduwaju.pdf
    • https://expobar.vn/app/webroot/files/images/pages/files/zogedijewegujuparusala.pdf
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f337041109---43564426156.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb6495ee6fb---woluserovetopajabobize.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/6d3e70daa1128ccd1596f47d3f46040c/manoxiwegunopuloro.pdf
    • https://baxsporthorses.nl/userfiles/file/92653476291.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/f605c7c7477f161d5c45ad28415c1417/kadilo.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f5908e375---junakizale.pdf
    • https://mszukam.pl/dat//file/judidogezimupidin.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/s1h319qj6u074hm4h6ru7h1f93/25421902499.pdf
    • http://atdawnwelift.com/userfiles/file/39026472718.pdf
    • http://digivideos.net/ckfinder/userfiles/files/tepuxobuzotawenenogamu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=ecpm+by+country
    • 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_off00010186.bin
8bd5c54e9e120cb0334d7430232cb9faf1a0b93e7838370d0ec009b131f481f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10186 17408 bytes
font_01_sfnt_off00012f0b.bin
f2533a6aff708dcbb5a43b809a2331e86ebb35ff0463d77a70253af15f8f9ea9
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F0B 10272 bytes
font_02_sfnt_off000145eb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x145EB 16792 bytes