Malicious PDF — malware analysis report

Static analysis result for SHA-256 848161e83ca1cead…

MALICIOUS

PDF

102.2 KB Created: 2021-07-29 18:00:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 91c9f53aa365448ea9bfcb1598a3e56d SHA-1: 5cc784d2fd98683c4a0fbcf7cffe088b517ada4d SHA-256: 848161e83ca1ceada358afc39b5f0fe13c94f91836ab5afa25995b529b6ca362
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. These links likely serve as lures for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/4d06686ec152abad0be6b1f2a0771746/28428162793.pdf
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/751e87ada255f9dd87206da4d3986781/69480944759.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/c8db451860cb9091c211fdd025595fb6/64666752636.pdf
    • http://bright-inter.com/file_media/file_image/file/famamujatefanomatinujulax.pdf
    • http://al-bandak.com/userfiles/file/35719897261.pdf
    • http://softwarefactory.nl/images/file/43806804385.pdf
    • http://staresecurity.com/userfiles/file/wuvefa.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d37a1f6db21---xafogizado.pdf
    • http://topenglish.sk/app/webroot/gallery/files/56073703610.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160764ff70a4c6---nozudojubeworo.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3028c306a5---noxizabefubebi.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d583d5300---musefufijefefopuratizop.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/e75762112f0c234cb6d2aa18a94cba66/pirufegozavelifuwewibega.pdf
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/90513e217ea3d9e4e85a94c3576bfca5/wasodesojigutedaparoxisov.pdf
    • http://softwarefactory.nl/images/file/31904756415.pdf
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/b54b749feefa3267522d0120898e827e/siwugixazoj.pdf
    • http://smithmaloney.com/clients/3/32/32eae1a42220421eddab78da2f55685d/File/55009317394.pdf
    • http://floral-design-lindgens.de/userfiles/file/4368748322.pdf
    • http://meble-tk.pl/userfiles/file/nadakisoguxugubizefubet.pdf
    • http://arch-teh.com/pic/userfile/lijin.pdf
    • http://hndgyl.com/v15/Upload/file/2021651057566671.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=electrical+engineering+question+papers+with+answers+pdf
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010f21.bin
d9b6a10f468414fe9e695a20a81af2a247d0a63fc6d2f48025b4d35440467e34
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F21 18400 bytes
font_01_sfnt_off00013fe7.bin
a3707ec9fce519e399799831bdb5c8b64653d4365fcbb927bb054175b66a5597
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FE7 11212 bytes
font_02_sfnt_off00015992.bin
7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x15992 16312 bytes
font_03_sfnt_off00016f9d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16F9D 16792 bytes