Malicious PDF — malware analysis report

Static analysis result for SHA-256 a38a982185ec153d…

MALICIOUS

PDF

163.1 KB Created: 2021-07-03 04:08:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6b9de8cd34c58d0bda2052bc34ed2134 SHA-1: a910a4c2c94204795e5dc7e92de519399c8acb6c SHA-256: a38a982185ec153d64c3fda94203ea57b9e676934c898c2646c5637b538a10fe
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to compromised CMS upload directories and disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9511

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 http://dynamic1984.com/user_file/file/nuzuposizid.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076d89322c9c---22224175265.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/pdqhl2cglop3l3s62dec8rdn8j/50590561653.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c53d3f7aead---mukegivikuvubu.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083c8454ca3e---gusalurel.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/cdd8e30c18b281bfa7b33bbe435cd80c/40435944852.pdf
    • http://tasarimak.net/ckfinder/userfiles/files/37503224107.pdf
    • http://berallebags.com/UploadFiles/FCKeditor/20210521135148.pdf
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/salutilibuliviguwunevi.pdf
    • http://activesolutionelectric.com/images/file/wadagilaxivigaji.pdf
    • http://aygroupmuh.com/image/files/gaporavumeras.pdf
    • http://analogsys.com/uploaded/file/154431115060a121ce04e3b.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2a4b37d4e---fawariz.pdf
    • https://twr1115.net/files/fckeditor/file/39606399625.pdf
    • http://dyglas.com/userData/board/file/83321015058.pdf
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/68c25cada5ca8b4cfb6159a952f760eb/zijigufe.pdf
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/6m6oank56ntnj6h7oth4pv4tq4/83233194132.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5171a4718---25959064585.pdf
    • http://automozg.by/upload/editor/files/zisida.pdf
    • http://zulaikhatextile.com/userfiles/files/81732332694.pdf
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ec6bc769e4---35133282560.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/21d6a72c7dd6495370ffcd508a0c0773/47903595379.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b98f279ef3b---bikobalifupefumajubiz.pdf
    • http://ipceurope.com/assets/file/61338562776.pdf
    • http://xn--l3cbpp3gh4a5g5c.com/userfiles/files/vipanumesoxadofa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=blinded+by+the+light+1+hour
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001f309.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1F309 16792 bytes
font_01_sfnt_off00020b16.bin
184a936bd1ce5dff700adc4e6a12c67a52a21ba3f6bd4f31defed58e18ed8b92
pdf-font-stream PDF embedded font (sfnt) at offset 0x20B16 1856 bytes
font_02_sfnt_off000213ba.bin
ed41064b75087cb54312ddbfa275ff6a47a0b6f9057743cc365ccf3f9456ec33
pdf-font-stream PDF embedded font (sfnt) at offset 0x213BA 23872 bytes
font_03_sfnt_off00024e00.bin
94ada888842219b54f0bff61c05754c95ee5bc28b4560123b174b2ad5ef12220
pdf-font-stream PDF embedded font (sfnt) at offset 0x24E00 16144 bytes
font_04_sfnt_off00026387.bin
ebd437b7b4bef0d6000b19e3c140967429bb8c3d83403c224f1bcfd1ad82c499
pdf-font-stream PDF embedded font (sfnt) at offset 0x26387 10656 bytes